ARCH: AUDIT: implement syscall_get_arch for all arches

For all arches which support audit implement syscall_get_arch()
They are all pretty easy and straight forward, stolen from how the call
to audit_syscall_entry() determines the arch.

Based-on-patch-by: Richard Briggs <rgb@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>
Cc: linux-ia64@vger.kernel.org
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: linux-mips@linux-mips.org
Cc: linux@lists.openrisc.net
Cc: linux-parisc@vger.kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: sparclinux@vger.kernel.org

arch/ia64/include/asm/syscall.h

@@ -13,6 +13,7 @@
 #ifndef _ASM_SYSCALL_H
 #define _ASM_SYSCALL_H	1
 
+#include <uapi/linux/audit.h>
 #include <linux/sched.h>
 #include <linux/err.h>
 
@@ -79,4 +80,9 @@ static inline void syscall_set_arguments(struct task_struct *task,
 
 	ia64_syscall_get_set_arguments(task, regs, i, n, args, 1);
 }
+
+static inline int syscall_get_arch(void)
+{
+	return AUDIT_ARCH_IA64;
+}
 #endif	/* _ASM_SYSCALL_H */