bug#47598: cperl-mode: Highlighting confused with ternary and -x

[E. Choroba]

When combining the ternary operator with file tests using the default 
argument, cperl-mode gets confused.

For example:

my $f = -f ? 'file'
      : -l ? [readlink]
      : -d ? 'dir'
           : 'unknown';

It seems to think the ?'s are not part of a ternary operator, but rather a 
match-once operator. Note that m?? without m results in a syntax error since 
Perl 5.22.

Ch.