usb: dwc3: Resume parent before resuming child device while in host mode

Consider a scenario where a peripheral connected to the host gets
runtime suspended because of no bus activity. When the device tries
to enter suspend/deep sleep from this state and if it fails to suspend
PM framework calls pm_resume of the suspended device. Currently
xhci_plat_resume will call xhci_resume but it will fail since the parent
(dwc3) is not resumed.

Fix this by resuming glue driver and core by performing pm_runtime_resume
on xhci-plat device.

Change-Id: I71349fa88bce65fa9ec9bceb7c42ef79db763a84
Signed-off-by: Pratham Pratap <prathampratap@codeaurora.org>