intel: Fix segfault in intel_texsubimage_tiled_memcpy

The function segfaulted when a game called glTexSubImage2D on a texture
with internalformat/format/type = GL_SLUMINANCE8/GL_BGRA/GL_UNSIGNED_BYTE.

The function only supports MESA_FORMAT_ARGB8888 and returns early if it
detects an unsupported format. Clearly, its detection condition was
insufficient. This patch fixes it to explicity check for
MESA_FORMAT_ARGB8888.

Note: This is a candidate for the 9.0 branch (fixes 413c491).
Reviewed-and-tested-by: Kenneth Graunke <kenneth@whitecape.org>
Acked-by: Paul Berry <stereotype441@gmail.com>
Signed-off-by: Chad Versace <chad.versace@linux.intel.com>

src/mesa/drivers/dri/intel/intel_tex_subimage.c

@@ -199,8 +199,7 @@ intel_texsubimage_tiled_memcpy(struct gl_context * ctx,
     * varying the arithmetic loop below.
     */
    if (!intel->has_llc ||
-       format != GL_BGRA ||
-       type != GL_UNSIGNED_BYTE ||
+       texImage->TexFormat != MESA_FORMAT_ARGB8888 ||
        texImage->TexObject->Target != GL_TEXTURE_2D ||
        texImage->Level != 0 ||
        pixels == NULL ||