sh: sh7757: switch RSPI clock to dev ID match

Switch the RSPI MSTP clock on SH7757 from a con ID match to a dev ID
match, so we can start looking it up using clk_get() with a NULL ID.

Signed-off-by: Geert Uytterhoeven <geert+renesas@linux-m68k.org>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>