Implemented subregion clears.
The quad layout had to be disabled to depth/stencil textures,
as it was not expected by dEQP.

Passes all tests in api.image_clearing.dedicated_allocation.
- partial_clear_color_attachment.*
- partial_clear_depth_stencil_attachment.*

Bug b/119621736

Change-Id: I9e854eceeef4a72b2ae507d62dbdbfa0b56c96f3
Reviewed-on: https://swiftshader-review.googlesource.com/c/23829Tested-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Chris Forbes <chrisforbes@google.com>
Reviewed-by: Corentin Wallez <cwallez@google.com>