MAC/do: Rename rule_is_valid() => rule_applies()

[olce]

Summary

This revision is part of a series. Click on the Stack tab below to see the context.
This series has also been squeezed into D47633 to provide an overall view.

Commit message:
This function checks whether a rule applies in the current context, i.e., if the subject's users/groups match that of the rule.
By contrast, it doesn't check if the rule as specified by the user is valid (i.e., consistent).

[emaste]

Commit message should explain why something was done not (just) what; in this case it the reason is fairly clear from context but still needs the reader to look at the change and understand.

[bapt]

agreed with @emaste on the why I personnally find rule_is_valid easier to understand then rule_applies, but still find rule_applies clear enough so I am ok with the change itself

[olce]

In D47592#1086653, @emaste wrote:

Commit message should explain why something was done not (just) what; in this case it the reason is fairly clear from context but still needs the reader to look at the change and understand.

Of course. I just thought that this was obvious here (and the diff is tiny). Will add to the description.