xen/arm: define PAGE_HYPERVISOR as WRITEALLOC

Use stage 1 attribute indexes for PAGE_HYPERVISOR, the appriopriate one
for normal memory hypervisor mappings in Xen is WRITEALLOC.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>

xen/include/asm-arm/page.h

@@ -58,7 +58,7 @@
 #define DEV_WC        BUFFERABLE
 #define DEV_CACHED    WRITEBACK
 
-#define PAGE_HYPERVISOR         (MATTR_MEM)
+#define PAGE_HYPERVISOR         (WRITEALLOC)
 #define PAGE_HYPERVISOR_NOCACHE (DEV_SHARED)
 #define PAGE_HYPERVISOR_WC      (DEV_WC)
 #define MAP_SMALL_PAGES         PAGE_HYPERVISOR