power: smb1351-charger: Fix the float voltage unit passed to its set method

Correction in the value being passed to the float_voltage_set method
in the smb1351 parallel_set_property function. The value being passed
is in uV range whereas the expected value lies in the mV range.

Change-Id: If04468062f973e1f102fd2f943271b2a133e3d8b
Signed-off-by: Umang Agrawal <uagrawal@codeaurora.org>