ppc64: Always pass non segment faults on the 0xc region up to do_page_fault

arch/ppc64/kernel/head.S

@@ -897,18 +897,8 @@ _GLOBAL(do_stab_bolted)
 
 	mfspr   r22,DSISR
 	andis.  r22,r22,0x0020
-	bne+    2f
-	ld	r22,8(r21)	/* get SRR1 */
-	andi.	r22,r22,MSR_PR	/* check if from user */
-	bne+	stab_bolted_user_return  /* from user, send the error on up */
-#if 0
-	li	r3,0
-#ifdef CONFIG_XMON
-	bl	.xmon
-#endif
-1:	b	1b
-#endif
-2:
+	beq-	stab_bolted_user_return
+
 	/* (((ea >> 28) & 0x1fff) << 15) | (ea >> 60) */
 	mfspr	r21,DAR
 	rldicl  r20,r21,36,32   /* Permits a full 32b of ESID */