[PARISC] Kill off the last vestiges of ASM_PAGE_SIZE

Sam's previous patch missed a few uses of ASM_PAGE_SIZE.
Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>

arch/parisc/kernel/head.S

@@ -95,7 +95,7 @@ $bss_loop:
 
 1:
 	stw		%r3,0(%r4)
-	ldo		(ASM_PAGE_SIZE >> PxD_VALUE_SHIFT)(%r3),%r3
+	ldo		(PAGE_SIZE >> PxD_VALUE_SHIFT)(%r3),%r3
 	addib,>		-1,%r1,1b
 #if PT_NLEVELS == 3
 	ldo             ASM_PMD_ENTRY_SIZE(%r4),%r4