i2c: designware: Modify timing parameters for amdpsp mailbox

Adjust retry period and timeout values for x86-PSP mailbox based on the
typical I2C traffic generated by PSP. In order to limit the possibility
of timeouts, x86 should reduce the interval between retries as well as
increase overall time after which it gives up.

Signed-off-by: Jan Dabros <jsd@semihalf.com>
Acked-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Wolfram Sang <wsa@kernel.org>