powerpc/40x: Refactor exception entry macros by using head_32.h

Refactor exception entry macros by using the ones defined in head_32.h

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/head_32.h

@@ -59,8 +59,12 @@
 	stw	r1,GPR1(r11)
 	stw	r1,0(r11)
 	tovirt(r1,r11)			/* set new kernel sp */
+#ifdef CONFIG_40x
+	rlwinm	r9,r9,0,14,12		/* clear MSR_WE (necessary?) */
+#else
 	li	r10,MSR_KERNEL & ~(MSR_IR|MSR_DR) /* can take exceptions */
 	MTMSRD(r10)			/* (except for mach check in rtas) */
+#endif
 	stw	r0,GPR0(r11)
 	lis	r10,STACK_FRAME_REGS_MARKER@ha /* exception frame marker */
 	addi	r10,r10,STACK_FRAME_REGS_MARKER@l