drm/i915/query: Expose memory regions through the query uAPI

drm/i915/query: Expose memory regions through the query uAPI

Returns the available memory region areas supported by the HW.

v2(Daniel & Jason):
    - Add some kernel-doc, including example usage.
    - Drop all the extra rsvd
v3(Jason & Tvrtko)
    - add back rsvd

Signed-off-by: Abdiel Janulgue <[email protected]>
Signed-off-by: Matthew Auld <[email protected]>
Cc: Joonas Lahtinen <[email protected]>
Cc: Thomas Hellström <[email protected]>
Cc: Daniele Ceraolo Spurio <[email protected]>
Cc: Lionel Landwerlin <[email protected]>
Cc: Jon Bloomfield <[email protected]>
Cc: Jordan Justen <[email protected]>
Cc: Daniel Vetter <[email protected]>
Cc: Kenneth Graunke <[email protected]>
Cc: Jason Ekstrand <[email protected]>
Cc: Dave Airlie <[email protected]>
Cc: [email protected]
Cc: [email protected]
Reviewed-by: Kenneth Graunke <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]