tu,freedreno: Forbid blit event for R8G8_SRGB due to gpu faults
What does this MR do and why?
Same cause as for other R8G8 formats - msaa resolve via blit event causes gpu fault.
Fixes:
dEQP-VK.api.image_clearing.*.clear_color_attachment.*.r8g8_srgb_*
Cc: mesa-stable