ipq8064: pinctrl: Fixed missing RGMII pincontrol definitions

Add missing gpio definition for mdio and rgmii2.

Signed-off-by: Ram Chandra Jangir <rjangir@codeaurora.org>
Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Link: https://lore.kernel.org/r/20200219175940.744-1-ansuelsmth@gmail.com
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>