Discussion while adding the blackpill_f401ce board definition brought
up a few issues with the blackpill_f411ce board definition, which are
addressed in this commit:
* doc/index.rst had a typo
* support/openocd.cfg was incorrectly using the f4discovery profile,
which was fixed by using a custom profile for the SoC instead
* removed SoC from blackpill_f411ce.dts compatible line
* added support for jlink flash option
Signed-off-by: Kalyan Sriram <coder.kalyan@gmail.com>
