dm: cache: add the pl310 cache controller driver

Add a PL310 cache controller driver that is usually found on
ARMv7(32-bit) devices. The driver configures the cache settings that can
be found in the device tree files.

This initial revision only configures basic settings(data & instruction
prefetch, shared-override, data & tag latency). I believe these are the
settings that affect performance the most. Comprehensive settings can be
done by the OS.

Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Dinh Nguyen <dinguyen@kernel.org>