Split the driver to three parts: core, I²C, SPI.
No functional change intended.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20200407173849.43628-9-andriy.shevchenko@linux.intel.comSigned-off-by: Linus Walleij <linus.walleij@linaro.org>