ARM: OMAP2+: omap-usb-host: Get rid of platform_data from struct usbhs_phy_data

The platform data bits can be inferred from the other members of
struct usbhs_phy_data. So get rid of the platform_data member.

Build the platform data for the PHY device in usbhs_init_phys() instead.

Acked-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>