USB: gadget: Remove spoof disconnect workaround in ci13xxx_msm

The spoof disconnect workaround puts PHY in non-driving mode after
pull-up is disabled.  Some times pull-up is not getting enabled when
PHY is in non-driving mode.  As this workaround is not applicable for
28-nm PHY, remove it.

CRs-Fixed: 302394
Signed-off-by: Pavankumar Kondeti <pkondeti@codeaurora.org>