usb: renesas_usbhs: Add reset_control

R-Car Gen3 needs to deassert resets of both host and peripheral.
Since [eo]hci-platform is possible to assert the reset(s) when
the probing failed, renesas_usbhs driver doesn't work correctly
regardless of finished probing. To fix this issue, this patch adds
reset_control on this renesas_usbhs driver.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>