usb: gadget: udc: renesas_usb3: Fix soc_device_match() abuse

soc_device_match() is intended as a last resort, to handle e.g. quirks
that cannot be handled by matching based on a compatible value.

As the device nodes for the Renesas USB 3.0 Peripheral Controller on
R-Car E3 and RZ/G2E do have SoC-specific compatible values, the latter
can and should be used to match against these devices.

This also fixes support for the USB 3.0 Peripheral Controller on the
R-Car E3e (R8A779M6) SoC, which is a different grading of the R-Car E3
(R8A77990) SoC, using the same SoC-specific compatible value.

Fixes: 30025efa ("usb: gadget: udc: renesas_usb3: add support for r8a77990")
Fixes: 546970fd

 ("usb: gadget: udc: renesas_usb3: add support for r8a774c0")
Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/760981fb4cd110d7cbfc9dcffa365e7c8b25c6e5.1628696960.git.geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>