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/drivers/atm/horizon.c b/drivers/atm/horizon.c
index 584aa88..2bf1ef1 100644
--- a/drivers/atm/horizon.c
+++ b/drivers/atm/horizon.c
@@ -2884,12 +2884,7 @@ static struct pci_driver hrz_driver = {
 /********** module entry **********/
 
 static int __init hrz_module_init (void) {
-  // sanity check - cast is needed since printk does not support %Zu
-  if (sizeof(struct MEMMAP) != 128*1024/4) {
-    PRINTK (KERN_ERR, "Fix struct MEMMAP (is %lu fakewords).",
-	    (unsigned long) sizeof(struct MEMMAP));
-    return -ENOMEM;
-  }
+  BUILD_BUG_ON(sizeof(struct MEMMAP) != 128*1024/4);
   
   show_version();