This is a refactoring in preparation of cleaning up the handling
of key specific subcompletions.
The new `__docker_map_key_of_current_option()` function will be used
instead of the `__docker_map_key_of_current_option()` idiom in the
following commit.
As this function is very specific, checks using it should be executed
before those checking for `$prev`.
This commit just moves the checks without any modification.
Signed-off-by: Harald Albers <github@albersweb.de>
Upstream-commit: 904481becd
Component: cli
7e815e8fc6