sparc: Align clone and signal stacks to 16 bytes.

This is mandatory for 64-bit processes, and doing it also for 32-bit
processes saves a conditional in the compat case.

This fixes the glibc/nptl/tst-stdio1 test case, as well
as many others, on 64-bit.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc/kernel/signal_32.c b/arch/sparc/kernel/signal_32.c
index 7ce1a10..9882df9 100644
--- a/arch/sparc/kernel/signal_32.c
+++ b/arch/sparc/kernel/signal_32.c
@@ -267,15 +267,17 @@
 			sp = current->sas_ss_sp + current->sas_ss_size;
 	}
 
+	sp -= framesize;
+
 	/* Always align the stack frame.  This handles two cases.  First,
 	 * sigaltstack need not be mindful of platform specific stack
 	 * alignment.  Second, if we took this signal because the stack
 	 * is not aligned properly, we'd like to take the signal cleanly
 	 * and report that.
 	 */
-	sp &= ~7UL;
+	sp &= ~15UL;
 
-	return (void __user *)(sp - framesize);
+	return (void __user *) sp;
 }
 
 static inline int