iris: Avoid fast-clear with incompatible view

iris: Avoid fast-clear with incompatible view

For rendering operations, avoid adding or using fast-cleared blocks if
the render format is incompatible with the clear color interpretation.
Note that the clear color is currently interpreted through the
resource's surface format.

Makes iris pass subtests of the fcc-write-after-clear piglit test:

* UNORM -> SNORM, partial block on gen8+.
* linear -> sRGB, partial block on gen9+.
* UNORM -> SNORM, full block on gen12.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4972>