drm/i915/gvt: add resolution definition for vGPU type

This assigns resolution definition for each vGPU type. For smaller
resource type we should limit max resolution, so e.g limit to 1024x768
for 64M type, others are still default to 1920x1200.

v2: Fix for actual 1920x1200 resolution

Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>