i2c: designware: Don't set SCL timings and speed mode when in slave mode

According to data sheet SCL timing parameters and DW_IC_CON SPEED mode
bits are not used when operating in slave mode.

Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Tested-by: Luis Oliveira <lolivei@synopsys.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
2 files changed