Reported by Summum Bonum.
* tests/synclines.at: Fix Perl invocation: its -f is not like sed's.
# distcc[35882] (dcc_connect_by_name) ERROR: failed to look up host "chrisimac": Unknown host
# distcc[35882] Warning: failed to distribute input.c to chrisimac/4, running locally instead
# distcc[35882] (dcc_connect_by_name) ERROR: failed to look up host "chrisimac": Unknown host
# distcc[35882] Warning: failed to distribute input.c to chrisimac/4, running locally instead
-AT_CHECK([[perl -p -0777 -f - stderr <<\EOF
+AT_CHECK([[perl -p -0777 - stderr <<\EOF
s/^distcc\[\d+\] .*\n//gm;
s/^([^:]*:\d+)[.:][^:]*:(.*)$/$][1:$][2/gm;
s/^([^:]*:\d+:)[^#]*( #error)/$][1$][2/gm;
s/^distcc\[\d+\] .*\n//gm;
s/^([^:]*:\d+)[.:][^:]*:(.*)$/$][1:$][2/gm;
s/^([^:]*:\d+:)[^#]*( #error)/$][1$][2/gm;