powerpc: Use SPRN_xxx rather than xxx for SPR numbers

This changes symbols like HID0, SPRG3, SRR0, SRR1 etc. that refer to
special purpose registers to SPRN_HID0, SPRN_SPRG3, etc.  Using the
SPRN_ symbols clutters the namespace less, and the forthcoming merge
of asm/processor.h and asm/reg.h is going to remove the non-SPRN_
versions.
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/ppc64/kernel/pmc.c

@@ -70,7 +70,7 @@ void power4_enable_pmcs(void)
 {
 	unsigned long hid0;
 
-	hid0 = mfspr(HID0);
+	hid0 = mfspr(SPRN_HID0);
 	hid0 |= 1UL << (63 - 20);
 
 	/* POWER4 requires the following sequence */
@@ -83,6 +83,6 @@ void power4_enable_pmcs(void)
 		"mfspr     %0, %1\n"
 		"mfspr     %0, %1\n"
 		"mfspr     %0, %1\n"
-		"isync" : "=&r" (hid0) : "i" (HID0), "0" (hid0):
+		"isync" : "=&r" (hid0) : "i" (SPRN_HID0), "0" (hid0):
 		"memory");
 }