drm/tests/drm_buddy: add alloc_range_bias test

drm/tests/drm_buddy: add alloc_range_bias test

Sanity check range bias with DRM_BUDDY_RANGE_ALLOCATION.

v2:
  - Be consistent with u32 here.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Arunpravin Paneer Selvam <Arunpravin.PaneerSelvam@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240219121851.25774-6-matthew.auld@intel.com
Signed-off-by: Christian König <christian.koenig@amd.com>