[S390] Inline assembly cleanup.

Major cleanup of all s390 inline assemblies. They now have a common
coding style. Quite a few have been shortened, mainly by using register
asm variables. Use of the EX_TABLE macro helps  as well. The atomic ops,
bit ops and locking inlines new use the Q-constraint if a newer gcc
is used.  That results in slightly better code.

Thanks to Christian Borntraeger for proof reading the changes.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/kernel/time.c b/arch/s390/kernel/time.c
index 74e6178..1981c61 100644
--- a/arch/s390/kernel/time.c
+++ b/arch/s390/kernel/time.c
@@ -351,10 +351,12 @@
 	int cc;
 
         /* kick the TOD clock */
-        asm volatile ("STCK 0(%1)\n\t"
-                      "IPM  %0\n\t"
-                      "SRL  %0,28" : "=r" (cc) : "a" (&init_timer_cc) 
-				   : "memory", "cc");
+	asm volatile(
+		"	stck	0(%2)\n"
+		"	ipm	%0\n"
+		"	srl	%0,28"
+		: "=d" (cc), "=m" (init_timer_cc)
+		: "a" (&init_timer_cc) : "cc");
         switch (cc) {
         case 0: /* clock in set state: all is fine */
                 break;