powerpc/64s: Fix KVM interrupt using wrong save area

The CTR register reload in the KVM interrupt path used the wrong save
area for SLB (and NMI) interrupts.

Fixes: 9600f26 ("powerpc/64s/exception: Move KVM test to common code")
Cc: [email protected] # v5.7+
Reported-by: Christian Zigotzky <[email protected]>
Signed-off-by: Nicholas Piggin <[email protected]>
Tested-by: Christian Zigotzky <[email protected]>
Signed-off-by: Michael Ellerman <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: npiggin

arch/powerpc/kernel/exceptions-64s.S

@@ -270,7 +270,7 @@ BEGIN_FTR_SECTION
 END_FTR_SECTION_IFSET(CPU_FTR_CFAR)
 	.endif
 
-	ld	r10,PACA_EXGEN+EX_CTR(r13)
+	ld	r10,IAREA+EX_CTR(r13)
 	mtctr	r10
 BEGIN_FTR_SECTION
 	ld	r10,IAREA+EX_PPR(r13)
@@ -298,7 +298,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR)
 
 	.if IKVM_SKIP
 89:	mtocrf	0x80,r9
-	ld	r10,PACA_EXGEN+EX_CTR(r13)
+	ld	r10,IAREA+EX_CTR(r13)
 	mtctr	r10
 	ld	r9,IAREA+EX_R9(r13)
 	ld	r10,IAREA+EX_R10(r13)