* src/fixits.h, src/fixits.c (fixits_empty): New.
* src/complain.c (deprecated_directive): Register the Wdeprecated
fixits only if -Wdeprecated was enabled, so that we don't apply
updates if the user didn't ask for them.
* src/main.c (main): If there were fixits, issue a warning suggesting
running with --update.
Free uniqstrs after the fixits, since the latter use the former.
* tests/headers.at, tests/input.at: Update expectations.
169fe80c7f