usb: dwc3-msm: Pass physical address for dummy GEVNTCNT to IPA

Currently the driver passes mapped address of the dummy GEVNTCNT
to IPA. But IPA expects this to be a physical address leading to
invalid access. Fix this by passing the physical address of the
directly allocated kernel memory for dummy GEVNTCNT.

Change-Id: I5a76ba4ac6dafeb2018f8c2052d2eb4a88f2af61
Signed-off-by: Ajay Agarwal <ajaya@codeaurora.org>