ENGR00212232-01 USB:fix otg can not work without phy power if VBUS removed

ENGR00212232-01 USB:fix otg can not work without phy power if VBUS removed

According to ticket TKT094250 :There is no VBUS supply or not supply for USB
PHY power 3p0,USB dp/dm is floating when there is no connection in device mode:
S/W can run the following flow to ensure the internal DP/DM linestate does not
change. These should be done before set SUSP/PHCD bit after detecting the VBUS
change from high to low.
clear HW_USBPHY_DEBUG_CLKGATE
loopback_utmi_dig_tst1 = 1
loopback_utmi_dig_tst0 = 0
loopback_tsti_tx_en = 1
loopback_tsti_tx_hiz = 0
loopback_tsti_tx_hs_mode = 0;

After detecting the VBUS or ID change (connected to a host or device), SW do:
set HW_USBPHY_DEBUG_CLKGATE back to 1
clear the loopback_XXXX signals above back to 0

Signed-off-by: make shi <b15407@freescale.com>