amdgpu_gfx_bit_to_me_queue has been unused since it was added in
commit 7470bfcf ("drm/amdgpu: add helper function for gfx queue/bitmap
transition")

Remove it.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>