usb: r8a66597-hcd: Add support for SH7723 USB host

R8A66597 is similar to SH7723 USB 2.0 Host/Function module.
In addition, the USB of SH7366 is compatible with SH7723.
It can support SH7723 USB host by changing Kconfig.

Signed-off-by: Yoshihiro Shimoda <shimoda.yoshihiro@renesas.com>
Acked-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>