drm/i915/gvt: don't include gvt.h from intel_gvt_mmio_table.h

intel_gvt_mmio_table.c has no need to include the massive
gvt.h. Simplify.

Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Reviewed-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230926121904.499888-2-jani.nikula@intel.com