usb_bam: Fix usb bam_type assignment during suspend

Driver incorrectly uses bam_mode (device/host) as bam_type
(dwc3/CI). This logic will work as long as bus-suspend
happens for dwc3 in device mode with BAM function but will
fail with CI core in device mode. However host mode BAM
pipes are no longer supported. Fix this by using proper
variable for bam_type instead of cur_bam_mode.

Change-Id: Id3b2bf3e578b5c339c46c940645b439dfafd28fb
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>