More precise error messages for moving unmanaged resource

[F16shen]

In my case, I don't have any constraint in the cluster , so the error message looks quite confusing.

Error: Unable to move resource 'xxxxx' using a location constraint. Current location of the resource may be affected by some other constraint.

Does this needs a test case?

[knet-ci-bot]

Can one of the admins verify this patch?

[tomjelinek]

test this please

[F16shen]

Thank you for the reply. I have fixed issue you mentioned @ondrejmular

[ondrejmular]

retest this please

[tomjelinek]

retest this please