anv: report error for invalid image storage format
When the caller requests an invalid format for image storage, anv asserts. Release builds access uninitialized memory, potentially causing a crash in the driver.
Returning an error and providing a null buffer/image allows the application to continue.
This works around an application bug in Hitman3 / Proton Experimental.
Suggested-by: Lionel Landwerlin lionel.g.landwerlin@intel.com Closes: #6998 (closed)