x86: also define AT_VECTOR_SIZE_ARCH

The patch introducing this left out x86-64, despite it also having
extra entries.

[ mingo@elte.hu: re-merged this to after the unification patches. ]
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

include/asm-x86/system.h

@@ -9,8 +9,14 @@
 #include <linux/kernel.h>
 #include <linux/irqflags.h>
 
+/* entries in ARCH_DLINFO: */
+#ifdef CONFIG_IA32_EMULATION
+# define AT_VECTOR_SIZE_ARCH 2
+#else
+# define AT_VECTOR_SIZE_ARCH 1
+#endif
+
 #ifdef CONFIG_X86_32
-#define AT_VECTOR_SIZE_ARCH 2 /* entries in ARCH_DLINFO */
 
 struct task_struct; /* one of the stranger aspects of C forward declarations */
 extern struct task_struct *FASTCALL(__switch_to(struct task_struct *prev,