Send helmv2-cli error messages to stderr

Script was sending error logs only on stdout
while other scripts down the line (eg. sysinv.helm.utils)
expected these error messages on stderr.

Test Plan:
PASS Delete armada deployment and use helm v2 list.
     Error msg on stderr.

Partial-Bug: 1999572

Signed-off-by: Leonardo Fagundes Luz Serrano <Leonardo.FagundesLuzSerrano@windriver.com>
Change-Id: Ic6cd2bd844382a47e9b1451ae7c3430951493da8

kubernetes/helm/centos/files/helmv2-cli.sh

@@ -63,6 +63,7 @@ function LOG {
 }
 function ERROR {
     MSG="ERROR"
+    echo "${MSG} $@" >&2
     LOG "${MSG} $@"
 }