linux-imx

drm/i915/gvt: Export intel_gvt_render_mmio_to_ring_id()

Since many emulation logic needs to convert the offset of ring registers
into ring id, we export it for other caller which might need it.

Signed-off-by: Zhi Wang <zhi.a.wang@intel.com>
(cherry picked from commit 62a6a53786fc4b4e7543cc63b704dbb3f7df4c0f)