pinctrl: aspeed-g5: Fix GPIOE1 typo

This prevented C20 from successfully being muxed as GPIO.

Fixes: 56e57cb6 (pinctrl: Add pinctrl-aspeed-g5 driver)
Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>