powerpc: Use MSR_64BIT in places

Use the new MSR_64BIT in a few places. Some of these are already ifdef'ed
for BOOKE vs BOOKS, but it's still clearer, MSR_SF does not immediately
parse as "MSR bit for 64bit".

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index cb71cf2..4a6a109 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -199,7 +199,7 @@
 	} else if (show_unhandled_signals &&
 		    unhandled_signal(current, signr) &&
 		    printk_ratelimit()) {
-			printk(regs->msr & MSR_SF ? fmt64 : fmt32,
+			printk(regs->msr & MSR_64BIT ? fmt64 : fmt32,
 				current->comm, current->pid, signr,
 				addr, regs->nip, regs->link, code);
 		}