Xapi_vdi.check_operation_error: checks for cbt_metadata VDI
Xapi_vdi.check_operation_error: checks for cbt_metadata VDI

Add checks for VDIs of type cbt_metadata: disallow a set of operations
on such VDIs.

Signed-off-by: Gabor Igloi <7535f5501fd71876c93d896691e178fd3a11cfbb@citrix.com>

srowe/xen-api,euanh/xen-api,srowe/xen-api,srowe/xen-api,euanh/xen-api,srowe/xen-api,euanh/xen-api,euanh/xen-api,euanh/xen-api,srowe/xen-api,euanh/xen-api