ia64: Fix Exec-Only stack patch so X can work again.

No pun intended, but X can't work if it can't turn on eXecute-permission
on the some data pages...

include/asm-ia64/pgtable.h

@@ -147,8 +147,8 @@
 #define __P011	PAGE_READONLY	/* ditto */
 #define __P100	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_X_RX)
 #define __P101	__pgprot(__ACCESS_BITS | _PAGE_PL_3 | _PAGE_AR_RX)
-#define __P110	PAGE_COPY
-#define __P111	PAGE_COPY
+#define __P110	PAGE_COPY_EXEC
+#define __P111	PAGE_COPY_EXEC
 
 #define __S000	PAGE_NONE
 #define __S001	PAGE_READONLY