lib/vsprintf.c: remove %Z support

Now that %z is standartised in C99 there is no reason to support %Z.
Unlike %L it doesn't even make format strings smaller.

Use BUILD_BUG_ON in a couple ATM drivers.

In case anyone didn't notice lib/vsprintf.o is about half of SLUB which
is in my opinion is quite an achievement.  Hopefully this patch inspires
someone else to trim vsprintf.c more.

Link: http://lkml.kernel.org/r/20170103230126.GA30170@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/net/appletalk/ddp.c b/net/appletalk/ddp.c
index 10d2bdc..465cc24 100644
--- a/net/appletalk/ddp.c
+++ b/net/appletalk/ddp.c
@@ -1656,7 +1656,7 @@ static int atalk_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
 	ddp->deh_dport = usat->sat_port;
 	ddp->deh_sport = at->src_port;
 
-	SOCK_DEBUG(sk, "SK %p: Copy user data (%Zd bytes).\n", sk, len);
+	SOCK_DEBUG(sk, "SK %p: Copy user data (%zd bytes).\n", sk, len);
 
 	err = memcpy_from_msg(skb_put(skb, len), msg, len);
 	if (err) {
@@ -1720,7 +1720,7 @@ static int atalk_sendmsg(struct socket *sock, struct msghdr *msg, size_t len)
 		 */
 		aarp_send_ddp(dev, skb, &usat->sat_addr, NULL);
 	}
-	SOCK_DEBUG(sk, "SK %p: Done write (%Zd).\n", sk, len);
+	SOCK_DEBUG(sk, "SK %p: Done write (%zd).\n", sk, len);
 
 out:
 	release_sock(sk);