[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/traps.c b/arch/s390/kernel/traps.c
index c4982c9..3eb4fab 100644
--- a/arch/s390/kernel/traps.c
+++ b/arch/s390/kernel/traps.c
@@ -597,8 +597,7 @@
 		local_irq_enable();
 
 	if (MACHINE_HAS_IEEE)
-		__asm__ volatile ("stfpc %0\n\t" 
-				  : "=m" (current->thread.fp_regs.fpc));
+		asm volatile("stfpc %0" : "=m" (current->thread.fp_regs.fpc));
 
 #ifdef CONFIG_MATHEMU
         else if (regs->psw.mask & PSW_MASK_PSTATE) {