usb: dwc3-msm: Change usb irq to level triggered

Currently power event irq and dp/dm hs phy irq are
configured as rising edge triggered. As per HPG
all usb interrupt are level triggered and active high.

Change-Id: I87bb6e8b7802751ea0a77fef71d3c2777bd39295
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>