ac/surface: remove the overallocation workaround for Vega12

not needed anymore (probably since the tile_swizzle fix)

Reviewed-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>

src/amd/common/ac_surface.c

@@ -1594,10 +1594,6 @@ static int gfx9_compute_surface(ADDR_HANDLE addrlib,
 			assert(0);
 	}
 
-	/* Temporary workaround to prevent VM faults and hangs. */
-	if (info->family == CHIP_VEGA12)
-		surf->fmask_size *= 8;
-
 	return 0;
 }