USB: ohci-jz4740: Remove obsolete driver

The ohci-platform driver can control the clock, while usb-nop-xceiv
as the PHY can control the vbus regulator. So this JZ4740-specific
glue is not needed anymore.

Signed-off-by: Maarten ter Huurne <maarten@treewalker.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Paul Cercueil <paul@crapouillou.net>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/13105/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>