ASoC: wcd9310: Enhance MBHC fake insert detection

Currently once we detect an insertion and check the microphone
voltage, if mic voltage is above a threshold (v_ins_hu) we say that it
was a fake insertion and we switch fake insertion detection to micbias
trigger right away.
This is too aggressive and causing other side effects.
Make delay and reduce default value of t_ins_complete from 1000ms to 250ms

CRs-fixed: 318771
Change-Id: I5288f1bb841284320d16a174de371cc35ac673b4
Signed-off-by: Joonwoo Park <joonwoop@codeaurora.org>