drm/vmwgfx: Modify the resource validation interface

Allow selecting interruptible or uninterruptible waits to match
expectations of callers.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Deepak Rawat <drawat@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>