Revert "usb: msm_otg: add charger notify API"

This reverts commit 99cef213.
Current code informs charger driver to draw 500ma on detecting
SDP Charger and doesn't revert its vote. With this change, on
not receiving any RESET from Host, device would keep charging
500ma until USB cable is disconnected.

CRs-Fixed: 446955
Change-Id: I1f3ed0005e1fff3595c1b3336e2be7432aeb7348
Signed-off-by: Mayank Rana <mrana@codeaurora.org>