All these functions declares and initializes variable ret with
'0' and without modifying 'ret' variable, it is returned.

This patch removes this redundancy and returns '0' directly.
Signed-off-by: Saiyam Doshi <saiyamdoshi.in@gmail.com>
Link: https://lore.kernel.org/r/20190909174541.GA22718@SDSigned-off-by: Mark Brown <broonie@kernel.org>