intel/isl: Implement D16_UNORM workarounds.

intel/isl: Implement D16_UNORM workarounds.

GEN:BUG:14010455700 (lineage 1808121037):

   "To avoid sporadic corruptions “Set 0x7010[9] when Depth Buffer
   Surface Format is D16_UNORM , surface type is not NULL & 1X_MSAA"

Required for fixing ttps://gitlab.freedesktop.org/mesa/mesa/issues/2501.

GEN:BUG:1806527549:

   "Set HIZ_CHICKEN (7018h) bit 13 = 1 when depth buffer is D16_UNORM."

This one could fix a GPU hang in some workloads.

v2: Implement WA in isl and add another similar WA (Jason).
v3: Add flushes before changing chicken registers (Jason)
v4: Depth flush and stall + end of pipe sync when changing registers
(Jason).

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3801>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3801>