i2c: pmcmsp: return message count on master_xfer success

Returning zero is wrong in this case.

Signed-off-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
Fixes: 1b144df1d7d6 ("i2c: New PMC MSP71xx TWI bus driver")
1 file changed