Add the missing bits to the yaml, dts, and Kconfig to enable GPIO pin
generation based on device tree.
Signed-off-by: Kumar Gala <kumar.gala@linaro.org>
FE310 is the name of one SoC out of a range of products in the SiFive
Freedom line. The FE310 SoC port in Zephyr is compatible with all of
these products, so rename the SoC to SiFive Freedom
Signed-off-by: Nathaniel Graff <nathaniel.graff@sifive.com>