usb: otg: OMAP4430: Add phy_suspend function pointer to twl4030_usb_data

Declare the .phy_suspend function pointer to twl4030_usb_data structure.
OMAP internal phy suspend function will be hooked though this function
pointer to use in the transceiver driver.

Signed-off-by: Hema HK <hemahk@ti.com>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>