Fix missing lookup() vendor method error for pxe_drac

In order to the pxe_drac to work with IPA ramdisks, the vendor interface
should expose the lookup() method. This patch is adding it to the list
of mapped vendor methods for that driver.

Closes-Bug: #1541858
Change-Id: I0cc13550bbf980ee48579d750120d4c33d1fe6a1

ironic/drivers/drac.py

@@ -52,6 +52,8 @@ class PXEDracDriver(base.BaseDriver):
                         'commit_bios_config': self.drac_vendor,
                         'abandon_bios_config': self.drac_vendor,
                         }
-        self.vendor = utils.MixinVendorInterface(self.mapping)
+        self.driver_passthru_mapping = {'lookup': self.iscsi_vendor}
+        self.vendor = utils.MixinVendorInterface(self.mapping,
+                                                 self.driver_passthru_mapping)
         self.inspect = inspector.Inspector.create_if_enabled(
             'PXEDracDriver')

releasenotes/notes/drac-missing-lookup-3ad98e918e1a852a.yaml

@@ -0,0 +1,4 @@
+---
+fixes:
+  - Add missing "lookup" method to the pxe_drac driver vendor interface
+    enabling it to be deployed using the IPA ramdisk.