[SPARC64]: Move signal compat bits to new header file.

Create asm-sparc64/compat_signal.h and stuff things there.

This avoids the "linux/compat.h includes asm/signal.h but
asm/signal.h needs compat_sigset_t which isn't defined yet"
problems introduced recently.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/arch/sparc64/kernel/signal32.c b/arch/sparc64/kernel/signal32.c
index 708ba9b..c45f21b 100644
--- a/arch/sparc64/kernel/signal32.c
+++ b/arch/sparc64/kernel/signal32.c
@@ -29,6 +29,7 @@
 #include <asm/psrcompat.h>
 #include <asm/fpumacro.h>
 #include <asm/visasm.h>
+#include <asm/compat_signal.h>
 
 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))