drm/i915: add gtt misalignment test

add test to check handling of misaligned offsets and sizes

v4:
	* remove spurious blank lines
	* explicitly cast intel_region_id to intel_memory_type in misaligned_pin
Reported-by: kernel test robot <lkp@intel.com>
v6:
	* use NEEDS_COMPACT_PT instead of hard coding for DG2
v7:
	* use i915_vma_unbind_unlocked in misalignment test
v8:
	* handle stolen smem region returning -ENODEV due to
	  uninitialized on some setups
	* avoid trying to test bad alignments on single page hole regions

Signed-off-by: Robert Beckett <bob.beckett@collabora.com>
Reviewed-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220218184752.7524-9-ramalingam.c@intel.com