i2c: designware-pci: Add support for Fast Mode Plus and High Speed Mode

Add support to configure HCNT, LCNT values for Fast Mode Plus and High
Speed Mode.

Signed-off-by: Lakshmi Sowjanya D <lakshmi.sowjanya.d@intel.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>