<feature>[vm]: set vm backing nosharepages if configured

Resolves: ZSTAC-64604

Change-Id: I687a6e67626e79706f7178757779746373797473
Signed-off-by: AlanJager <ye.zou@zstack.io>

Author: AlanJager

kvmagent/kvmagent/plugins/vm_plugin.py

@@ -4648,8 +4648,11 @@ def make_memory_backing():
             backing = e(root, 'memoryBacking')
             if cmd.useHugePage:
                 e(backing, "hugepages")
-                e(backing, "nosharepages")
                 e(backing, "allocation", attrib={'mode': 'immediate'})
+
+            if cmd.noSharePages or cmd.useHugePage:
+                e(backing, "nosharepages")
+
             if cmd.MemAccess in "shared":
                 # <access mode="shared|private"/>
                 e(backing, "access", attrib={'mode': 'shared'})