proc: export uncached bit properly in /proc/kpageflags

Fix the left-over old ifdef for PG_uncached in /proc/kpageflags.  Now it's
used by x86, too.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

fs/proc/page.c

@@ -146,7 +146,7 @@ u64 stable_page_flags(struct page *page)
 	u |= kpf_copy_bit(k, KPF_HWPOISON,	PG_hwpoison);
 #endif
 
-#ifdef CONFIG_IA64_UNCACHED_ALLOCATOR
+#ifdef CONFIG_ARCH_USES_PG_UNCACHED
 	u |= kpf_copy_bit(k, KPF_UNCACHED,	PG_uncached);
 #endif