powerpc: Free a PTE bit on ppc64 with 64K pages

This frees a PTE bit when using 64K pages on ppc64.  This is done
by getting rid of the separate _PAGE_HASHPTE bit.  Instead, we just test
if any of the 16 sub-page bits is set.  For non-combo pages (ie. real
64K pages), we set SUB0 and the location encoding in that field.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
diff --git a/include/asm-powerpc/pgtable-4k.h b/include/asm-powerpc/pgtable-4k.h
index 818e2ab..fd2090d 100644
--- a/include/asm-powerpc/pgtable-4k.h
+++ b/include/asm-powerpc/pgtable-4k.h
@@ -41,6 +41,7 @@
 #define PGDIR_MASK	(~(PGDIR_SIZE-1))
 
 /* PTE bits */
+#define _PAGE_HASHPTE	0x0400 /* software: pte has an associated HPTE */
 #define _PAGE_SECONDARY 0x8000 /* software: HPTE is in secondary group */
 #define _PAGE_GROUP_IX  0x7000 /* software: HPTE index within group */
 #define _PAGE_F_SECOND  _PAGE_SECONDARY