usb: dwc3: Prevent pipe_PowerDown transition during U1 exit

During U1 exit, the controller might send LFPS ping at the same
time when the P1 to P0 transition occurs(GUSB3PIPECTL[27] = '0').
The de-assertion of the pipe_TxElecIdle signal during the
pipe_PowerDown signal transition violates the PIPE specification.
Fix this by setting GUSB3PIPECTL[27] = '1' so that there is no
pipe_PowerDown transition during U1 exit. This fix is applicable
for DWC3 revision 3.10 or older.

Change-Id: I7708d42c0f8b67d315be59e9ff9f04ccb74b9b5c
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>