sna: Allow tiled memcpy on i386

With the split into per-swizzle functions, and with the forced
optimisation levels, it appears that i386 doesn't suffer so badly and
the tiled memcpy are a viable method.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

src/sna/kgem.c

@@ -985,15 +985,6 @@ static void kgem_init_swizzling(struct kgem *kgem)
 {
 	struct drm_i915_gem_get_tiling tiling;
 
-#ifndef __x86_64__
-	/* Between a register starved compiler emitting attrocious code
-	 * and the extra overhead in the kernel for managing the tight
-	 * 32-bit address space, unless we have a 64-bit system,
-	 * using memcpy_to_tiled_x() is extremely slow.
-	 */
-	return;
-#endif
-
 	if (kgem->gen < 050) /* bit17 swizzling :( */
 		return;