intel/vec4: Remove leftover code from Gen8+ removal.

Remove code missed in commit 2a49007411bb ("intel/vec4: Remove all
support for Gen8+ [v2]").

Fix defect reported by Coverity Scan.

Logically dead code (DEADCODE)
dead_error_begin: Execution cannot reach this statement:
mcs.swizzle = 80U;

Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6927>
1 file changed