fs: Fix close_on_exec pointer in alloc_fdtable

alloc_fdtable allocates space for the open_fds and close_on_exec
bitfields together, as 2 * nr / BITS_PER_BYTE.  close_on_exec needs to
point to open_fds + nr / BITS_PER_BYTE, not open_fds + nr /
BITS_PER_LONG, as introducted in 1fd36ad: Replace the fd_sets in
struct fdtable with an array of unsigned longs.

Signed-off-by: Bobby Powers <bobbypowers@gmail.com>
Link: http://lkml.kernel.org/r/1329888587-3087-1-git-send-email-bobbypowers@gmail.com
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

fs/file.c

@@ -179,7 +179,7 @@ static struct fdtable * alloc_fdtable(unsigned int nr)
 	if (!data)
 		goto out_arr;
 	fdt->open_fds = data;
-	data += nr / BITS_PER_LONG;
+	data += nr / BITS_PER_BYTE;
 	fdt->close_on_exec = data;
 	fdt->next = NULL;