powerpc: Fixup oddity in entry_32.S

When I "fixed" the CONFIG_TRACE_IRQFLAGS case on interrupt entry,
I screwed up a little bit with the test for user space vs. kernel.

The code is fine, there's just some dead code around it. I basically
removed the test and always create the added stack frame whether
coming from user or kernel since in any case we do need to save
a bunch of volatile registers or bad things would happen (we can
take page faults in the kernel for example).
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

arch/powerpc/kernel/entry_32.S

@@ -226,13 +226,7 @@ reenable_mmu:				/* re-enable mmu so we can */
 	stw	r3,16(r1)
 	stw	r4,20(r1)
 	stw	r5,24(r1)
-	andi.	r12,r12,MSR_PR
-	b	11f
 	bl	trace_hardirqs_off
-	b	12f
-11:
-	bl	trace_hardirqs_off
-12:
 	lwz	r5,24(r1)
 	lwz	r4,20(r1)
 	lwz	r3,16(r1)