USB: phy-msm-usb: Process HOST disconnect only after system RESUME

If Host Cable (ID_GND) is disconnected in system suspend then
it results in race between device removal and device pm_resume.
PM core does't handle this correctly and sometimes frees up
parent device before children are resumed. To avoid this race
make sure that system has resumed completely before handling
ID_FLOAT (or host cable disconnect) event.

CRs-fixed: 652870, 651561
Change-Id: Id0956a9677d819d3fa3f17f54965cae38f2ee31d
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>