ARM: dts: rmobile: Move the PHY reset GPIOs into PHY nodes

Both the RAVB and SH ether driver now support parsing the PHY reset
GPIOs from both the PHY nodes and the MAC nodes, move the reset GPIOs
back into the PHY nodes to minimize DT difference between U-Boot and
Linux.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>