boards: remove `CONFIG_PINCTRL` from defconfig files of FE310-based boards

This commit removes the y-selection of the `CONFIG_PINCTRL` Kconfig option
in FE310-based boards defconfig files.

It also makes drivers used in FE310 y-select `CONFIG_PINCTRL` if pinmuxing
is needed.

Signed-off-by: Filip Kokosinski <fkokosinski@antmicro.com>
6 files changed