extcon: max77693: Fix bug when detecting MHL/Dock-Audio with USB/TA cable

extcon: max77693: Fix bug when detecting MHL/Dock-Audio with USB/TA cable

This patch fix bug that muic couldn't detect MHL/Dock-Audio with USB/TA
cable on exception situation. I explain detail case on following:

When MHL(with USB/TA cable) or Dock-Audio with USB/TA cable is attached,
the MUIC device happen following two interrupt.
- 'MAX77693_MUIC_IRQ_INT1_ADC' for detecting MHL/Dock-Audio.
- 'MAX77693_MUIC_IRQ_INT2_CHGTYP' for detecting USB/TA cable connected to
MHL/Dock-Audio. Always, happen eariler MAX77693_MUIC_IRQ_INT1_ADC interrupt
than MAX77693_MUIC_IRQ_INT2_CHGTYP interrupt.

If user attach MHL with USB/TA cable and immediately detach MHL with USB/TA
cable before MAX77693_MUIC_IRQ_INT2_CHGTYP interrupt is happened, USB/TA
connected to MHL cable remain connected state to target. But USB/TA connected
to MHL cable isn't connected to target. user be faced with unusual action.
So, driver should check this situation in spite of that, previous charger type
is N/A.

Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>
Signed-off-by: Myungjoo Ham <myungjoo.ham@samsung.com>