Don't repeat the name of the warning in the sub messages. E.g.,
remove the second "[-Wother]" in the following message
foo.y:2.1-27: warning: %define variable 'parse.error' redefined [-Wother]
%define parse.error verbose
^~~~~~~~~~~~~~~~~~~~~~~~~~~
foo.y:1.1-27: previous definition [-Wother]
%define parse.error verbose
^~~~~~~~~~~~~~~~~~~~~~~~~~~
* src/complain.c (error_message): Don't print the warning type when
it's indented.
Adjust test cases.