[SPARC64]: Move DCACHE_ALIASING_POSSIBLE define to asm/page.h

This showed that arch/sparc64/kernel/ptrace.c was not getting
the define properly, and thus the code protected by this ifdef
was never actually compiled before.  So fix that too.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/asm-sparc64/pgalloc.h b/include/asm-sparc64/pgalloc.h
index b9b1914..a96067c 100644
--- a/include/asm-sparc64/pgalloc.h
+++ b/include/asm-sparc64/pgalloc.h
@@ -10,6 +10,7 @@
 #include <asm/spitfire.h>
 #include <asm/cpudata.h>
 #include <asm/cacheflush.h>
+#include <asm/page.h>
 
 /* Page table allocation/freeing. */
 #ifdef CONFIG_SMP