proc: fix PG_locked reporting in /proc/kpageflags

Expr always evaluates to zero.

Cc: Matt Mackall <mpm@selenic.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>

fs/proc/page.c

@@ -107,7 +107,7 @@ static ssize_t kpageflags_read(struct file *file, char __user *buf,
 		else
 			kflags = ppage->flags;
 
-		uflags = kpf_copy_bit(KPF_LOCKED, PG_locked, kflags) |
+		uflags = kpf_copy_bit(kflags, KPF_LOCKED, PG_locked) |
 			kpf_copy_bit(kflags, KPF_ERROR, PG_error) |
 			kpf_copy_bit(kflags, KPF_REFERENCED, PG_referenced) |
 			kpf_copy_bit(kflags, KPF_UPTODATE, PG_uptodate) |