qcom: smb138x: set the freq to 700Khz

700Khz is not a harmonic of the digital clock and is optimal enough
for all vbus ranges. Running the smb in the non harmonic freq range
is required for correct TDIE adc reporting.

Change-Id: Ib70d64cd72b7408474fd64df287f6404d3749764
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>