ARM: mach-shmobile: SH-Mobile AP4 support.

This adds preliminary support for the SH7372 (SH-Mobile AP4) CPU and
the AP4EVB reference board.

Only timer, serial console and NOR flash are supported at this point.
Support for the interrupt controller, pinmux support, clock framework
and runtime pm will be submitted as feature patches on top of this.

Signed-off-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>