Many files in the tree implement functions, but do not include the
header files which provide the prototypes for these functions. This
means conflicting prototypes remain undetected. Add the missing
includes.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

PXA is the only architecture that uses its own prototypes for
the gpio functions because it uses static inline variants of
these functions. For the sake of streamlining with other architectures
move them to a C file and use the generic gpio prototypes.

Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

The core support was brought by Marc and Sascha.
The cache choice was fixed by Luotao Fu.
Some gpio and devices addons were provided by Robert.

Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>