powerpc: Rename USER_ESID_BITS* to ESID_BITS*

Now we use ESID_BITS of kernel address to build proto vsid. So rename
USER_ESIT_BITS to ESID_BITS

Acked-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
CC: <stable@vger.kernel.org> [v3.8]
diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S
index b112359..200afa5 100644
--- a/arch/powerpc/kernel/exceptions-64s.S
+++ b/arch/powerpc/kernel/exceptions-64s.S
@@ -1472,7 +1472,7 @@
 	addi	r9,r9,(MAX_USER_CONTEXT + 1)@l
 
 	srdi	r10,r11,SID_SHIFT
-	rldimi  r10,r9,USER_ESID_BITS,0 /* proto vsid */
+	rldimi  r10,r9,ESID_BITS,0 /* proto vsid */
 	ASM_VSID_SCRAMBLE(r10, r9, 256M)
 	rldic	r9,r10,12,16	/* r9 = vsid << 12 */