usb: core: hcd: remove support for initializing a single PHY

With the new PHY wrapper in place we can now handle multiple PHYs.
Remove the code which handles only one generic PHY as this is now
covered (with support for multiple PHYs as well as suspend/resume
support) by the new PHY wrapper.

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Tested-by: Neil Armstrong <narmstrong@baylibre.con>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>