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>

arch/powerpc/include/asm/linkage.h

@@ -0,0 +1,13 @@
+#ifndef _ASM_POWERPC_LINKAGE_H
+#define _ASM_POWERPC_LINKAGE_H
+
+#ifdef CONFIG_PPC64
+#define cond_syscall(x) \
+	asm ("\t.weak " #x "\n\t.set " #x ", sys_ni_syscall\n"		\
+	     "\t.weak ." #x "\n\t.set ." #x ", .sys_ni_syscall\n")
+#define SYSCALL_ALIAS(alias, name)					\
+	asm ("\t.globl " #alias "\n\t.set " #alias ", " #name "\n"	\
+	     "\t.globl ." #alias "\n\t.set ." #alias ", ." #name)
+#endif
+
+#endif	/* _ASM_POWERPC_LINKAGE_H */