sh64: Fixup sh-sci build.

sh-sci needs asm/sci.h, borrow this from sh so we can build
again.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/include/asm-sh64/sci.h b/include/asm-sh64/sci.h
new file mode 100644
index 0000000..793c568
--- /dev/null
+++ b/include/asm-sh64/sci.h
@@ -0,0 +1 @@
+#include <asm-sh/sci.h>