usb: dwc3: core: Add shutdown callback for dwc3

This patch adds a shutdown callback to USB DWC core driver to ensure that
it is properly shutdown in reboot/shutdown path. This is required
where SMMU address translation is enabled like on SC7180
SoC and few others. If the hardware is still accessing memory after
SMMU translation is disabled as part of SMMU shutdown callback in
system reboot or shutdown path, then IOVAs(I/O virtual address)
which it was using will go on the bus as the physical addresses which
might result in unknown crashes (NoC/interconnect errors).

Acked-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Sandeep Maheswaram <sanm@codeaurora.org>
Link: https://lore.kernel.org/r/1618380209-20114-1-git-send-email-sanm@codeaurora.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>