consolidate cond_syscall and SYSCALL_ALIAS declarations

take them to asm/linkage.h, with default in linux/linkage.h

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/ia64/include/asm/linkage.h b/arch/ia64/include/asm/linkage.h
index ef22a45..7875757 100644
--- a/arch/ia64/include/asm/linkage.h
+++ b/arch/ia64/include/asm/linkage.h
@@ -11,4 +11,8 @@
 
 #endif
 
+#define cond_syscall(x) asm(".weak\t" #x "#\n" #x "#\t=\tsys_ni_syscall#")
+#define SYSCALL_ALIAS(alias, name)					\
+	asm ( #alias "# = " #name "#\n\t.globl " #alias "#")
+
 #endif