sh: Move hd64461.h to a more sensible location.

With the I/O rework for hd64461 we're down to a single header,
so move it by itself and get rid of the directory.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/include/asm-sh/hp6xx/io.h b/include/asm-sh/hp6xx/io.h
index 7317980..2044476 100644
--- a/include/asm-sh/hp6xx/io.h
+++ b/include/asm-sh/hp6xx/io.h
@@ -4,7 +4,7 @@
 /*
  * Nothing special here.. just use the generic cchip io routines.
  */
-#include <asm/hd64461/io.h>
+#include <asm/hd64461.h>
 
 #endif /* __ASM_SH_HP6XX_IO_H */