Revert "drm/amdkfd: New IOCTL to allocate queue GWS"

This reverts commit 1a058c33

.

This interface is still in too much flux.  Revert until
it's sorted out.

Acked-by: Oak Zeng <Oak.Zeng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>