sh-pfc: Support pinmux info in driver data instead of platform data

Pinmux information should be provided by the pinmux driver, not arch
code. Make it possible to do so by supporting pinmux information passed
through the driver_data field in the platform ID table. Platform data
will remain supported until all arch code has been converted.

Rename the sh_pfc_platform_data structure to sh_pfc_soc_info to reflect
this.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>