usb: dwc3: make sure UX_EXIT_PX is cleared

usb: dwc3: make sure UX_EXIT_PX is cleared

[ Upstream commit 1966b8657d058ecb95031809b607bf3fd1e01c10 ]

This bit is only supposed to be used with known
buggy PHYs, however some platforms might erroneously
set it. In order to avoid it, let's make sure this
bit is always cleared. If some PHY needs this, we
will need to add a quirk flag.

Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>