ANDROID: GKI: USB: Gadget: use padding for usb bam changes

Commit 487209ed ("drivers: soc: qcom: Add usb bam changes")
introduces new variables to struct usb_gadgets. Use the reserved fields
to address the CRC issues these cause.

Bug: 185290066
Bug: 185091725
Signed-off-by: Will McVicker <willmcvicker@google.com>
Change-Id: Ibe49253a026a3e5918051ca65536a9b5838291ed