The i.MX28 shares a lot of functionality with its predecessor, the
i.MX23 (formerly known as stm378x). This patch adds some files to support
both CPUs.

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

Separate i.MX23 clock handling to simplify the addition of the upcoming i.MX28.

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

These CPUs are called "i.MX", but they are of type STM378x from SigmaTel. They
do not share any devices with the other i.MX CPUs, so we need a separate
architecute directory to handle them without an ifdef hell in the native i.MX
files.

Signed-off-by: Juergen Beisert <jbe@pengutronix.de>