USB: phy-msm: Disable USB_BAM in host mode

USB_BAM is used only in peripheral mode. If a platform
has bam2bam functions enabled in peripheral mode then
reset routine i.e. msm_otg_reset enables USB_BAM in
host mode also. Since, host mode doesn't use bam2bam mode
disable the same as it may slow down DDR access by USB.

Change-Id: If3f358362c26447c91ea6f0081b5237b162123a1
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>