powerpc/mm: Use symbolic constants for filtering SRR1 bits on ISIs

This uses the newly defined constants for this rather than open-coded
numbers. There is a side effect on 64-bit which is to pass through
some of the new P9 bits which we didn't before.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

arch/powerpc/kernel/head_8xx.S

@@ -569,8 +569,8 @@ _ENTRY(DTLBMiss_jmp)
 InstructionTLBError:
 	EXCEPTION_PROLOG
 	mr	r4,r12
-	andis.	r5,r9,0x4820		/* Filter relevant SRR1 bits */
-	andis.	r10,r9,0x4000
+	andis.	r5,r9,DSISR_SRR1_MATCH_32S@h /* Filter relevant SRR1 bits */
+	andis.	r10,r9,SRR1_ISI_NOPT@h
 	beq+	1f
 	tlbie	r4
 itlbie: