bug#36420: perl-mode: apostrophe in sub name ruins colors

[積丹尼 Dan Jacobson]

All the lines after the main'ttfmod are in the wrong color.

#       Title:      TTFMOD.PL
#       Author:     M. Hosken
package ttfmod;

sub main'ttfmod {
    local($infile, $outfile, *fns, @must) = @_;

    # open files as binary.  Notice OUTFILE is opened for update not just write
    open(INFILE, "$infile") || die "Unable top open \"$infile\" for reading";
    binmode INFILE;
    open(OUTFILE, "+>$outfile") || die "Unable to open \"$outfile\" for 
writing";
    #....
}