consolidate kernel-side struct sigaction declarations

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/arch/sparc/include/asm/signal.h b/arch/sparc/include/asm/signal.h
index e188185..c33ce3f 100644
--- a/arch/sparc/include/asm/signal.h
+++ b/arch/sparc/include/asm/signal.h
@@ -22,6 +22,7 @@
 #define SA_STATIC_ALLOC         0x8000
 
 #define __ARCH_HAS_KA_RESTORER
+#define __ARCH_HAS_SA_RESTORER
 
 #endif /* !(__ASSEMBLY__) */
 #endif /* !(__SPARC_SIGNAL_H) */