Update architectures/firmware/sof-zephyr/rtos_layer/io_drivers/i2s/i2s_driver.rst

Co-authored-by: Deb Taylor <[email protected]>

Author: lgirdwood

architectures/firmware/sof-zephyr/rtos_layer/io_drivers/i2s/i2s_driver.rst

@@ -118,7 +118,7 @@ loopbacks (LBM, loopback mode) - the receiver always does see what the sender is
 
 Please note the following: 
 
- - all the parameters of transmitter and receiver, like number of channels, data rates 
+ - all the parameters of transmitter and receiver, like number of channels, data rates, and format must match each other
 and format, must match each other
  - the lines are connected internally, so LBM mode may be used even if the I2S pins are not 
 physically available