ASoC: wcd: don't stop 3sec polling if 0x159 bit4 is set

During slow insertion of headset 0x159 bit4 can be set, due to this
3sec polling gets stopped which inturn results in wrong detection. So
don't check for 0x159 bit 4 during 3sec polling.
Ensure btn_press_intr is false before starting detection process.

Change-Id: I525e49c96b7e14a667e6c853c09b0ea7ab363b5e
Signed-off-by: Yeleswarapu Nagaradhesh <nagaradh@codeaurora.org>