serial: clps711x: Driver refactor

This is a complex patch for refactoring CLPS711X serial driver.
Major changes:
- Eliminate <mach/hardware.h> usage.
- Devicetree support.

Signed-off-by: Alexander Shiyan <shc_work@mail.ru>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>