Bug fix for tagged mode output from 'p4 diff2'.
Diff2 is one of
the few (only?) commands to use variables of the form 'var' and
'var2' rather than 'var1' and 'var2'. Normally, if there's no
numeric suffix to a variable, P4Perl can assume it's looking at
the only instance of that variable in the output. In the case of
'p4 diff2', that's not true.
This change enables P4Perl to adapt to this change of circumstances
and convert a previously scalar member of the hash result into an
array member.