Update error message

In this commit, Updated error message "Node Feature Discovery (NFD)
Application is required." as NFD is a pre-requisite to
intel-device-plugins-operator application.
Also, a top level README file has been added.

TEST CASES:

PASSED: Build process is successful with creation of debian package.
        After package extraction confirmed the helm tar file is present.
PASSED: Tested application upload/apply/remove/delete in AIO-SX.
PASSED: Error raised "Node Feature Discovery (NFD) Application is
        required." when intel-device-plugins-operator application is
        applied without NFD.
PASSED: Label will not be removed when node-feature-discovery app is
        deleted.

Story: 2010604
Task: 50364

Change-Id: I1393e6e3b7f429ea9418fa1a42944a19f2db579b
Signed-off-by: Md Irshad Sheikh <mdirshad.sheikh@windriver.com>

README

@@ -0,0 +1,65 @@
+## Application app-intel-device-plugins
+This application provides the intel device plugins to the StarlingX
+
+Top Level Directory Structure
+
+app-intel-device-plugins
+├── bindep.txt
+├── debian_build_layer.cfg
+├── debian_iso_image.inc
+├── debian_pkg_dirs
+├── helm-charts
+│   ├── custom # contains customized helm package
+│   │   └── intel-device-plugins-secret-observer-helm # contains secret-observer helm package
+│   └── upstream # contains upstream hlem package
+│       ├── intel-device-plugins-dsa-helm # contains DSA plugin helm package
+│       ├── intel-device-plugins-gpu-helm # contains GPU plugin helm package
+│       ├── intel-device-plugins-operator-helm # contains oeprator helm package
+│       └── intel-device-plugins-qat-helm # contains QAT plugin helm package
+├── python3-k8sapp-intel-device-plugins-operator # contains python plugins of application life cycle management
+├── README
+├── requirements.txt
+├── stx-intel-device-plugins-operator-helm # helm package manager for the application
+├── test-requirements.txt
+└── tox.ini
+
+## Source
+Charts are based on
+<https://github.com/intel/helm-charts/releases>.
+
+## Installation step:
+1. Build a package
+    "build -c -p
+    intel-device-plugins-operator-helm,
+    intel-device-plugins-dsa-helm,
+    intel-device-plugins-gpu-helm,
+    intel-device-plugins-qat-helm,
+    intel-device-plugins-secret-observer-helm,
+    python3-k8sapp-intel-device-plugins-operator,
+    stx-intel-device-plugins-operator-helm"
+
+2. Extract the content of stx-intel-device-plugins-helm_*amd64.deb and check
+   if the helm tar file is present in the location temp/usr/local/share/application/helm
+
+   Extract using command.
+   dpkg -x stx-intel-device-plugins-helm_*amd64.deb temp
+
+3. In the QAT hardware lab, if tar file file does not exist at the location "/usr/local/share/application/helm", then copy the tar file.
+
+4. Upload the tar using command.
+    "system application-upload tar_file"
+
+5. Check the helm chart status using command.
+   "system helm-override-list intel-device-plugins-operator --long"
+
+6. If you want to install any of the helm chart, then make it enable using command.
+   "system helm-chart-attribute-modify [--enabled <true/false>] <app name> <chart name> <namespace>"
+
+   For example, run following command to enable QAT helm chart.
+   "system helm-chart-attribute-modify  --enabled true intel-device-plugins-operator intel-device-plugins-qat intel-device-plugins-operator"
+
+7. Apply the application using command. (Note: Make sure node-feature-discovery application should be applied first before applying intel-device-plugins-operator application.)
+   "system application-apply intel-device-plugins-operator"
+
+8. After applying the application, Operator and QAT pods will be running and status can be checked using command.
+   "kubectl get pods -n intel-device-plugins-operator"

python3-k8sapp-intel-device-plugins-operator/k8sapp_intel_device_plugins_operator/k8sapp_intel_device_plugins_operator/lifecycle/lifecycle_intel_device_plugins_operator.py

@@ -72,13 +72,7 @@ class IntelDevicePluginsAppLifecycleOperator(base.AppLifecycleOperator):
         if not nfd_installed:
             if self._is_nfd_required(app_op):
                 raise exception.LifecycleSemanticCheckException(
-                    "Node Feature Discovery (NFD) Application is required. "
-                    "You can bypass this check by setting the "
-                    f"{app_constants.HELM_NFD_REQUIRED_PARAM} parameter to "
-                    "False using overrides.")
-
-            LOG.info("Bypass flag for Node Feature Discovery (NFD) "
-                     "Application found.")
+                    "Node Feature Discovery (NFD) Application is required.")
 
     def _is_nfd_required(self, app_op):