Add a pin configuration API to all pin-related configuration to be
specified with a single macro and groups of pins to be configured
at one go.  Based on the PXA MFP implementation.

Cc: Alessandro Rubini <rubini@unipv.it>
Acked-by: NLinus Walleij <linus.walleij@stericsson.com>
Signed-off-by: NRabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>