We're about to add more options for commands behaviour, so let's give
a more generic name to the low-level kdb command registration function.

There are just various renames, no functional changes.
Signed-off-by: NAnton Vorontsov <anton.vorontsov@linaro.org>
Signed-off-by: NJohn Stultz <john.stultz@linaro.org>
Signed-off-by: NDaniel Thompson <daniel.thompson@linaro.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Signed-off-by: NJason Wessel <jason.wessel@windriver.com>