rm: simplify process_options()

* is_recursive() is already smart enough to check both -R and -r, so manually setting opt{"R"} is not required
* As a regression test I removed some subdirs, first using -r, then -R

bin/rm

@@ -196,8 +196,6 @@ sub process_options {
 		);
 	usage() unless $ret;
 
-	$opts{'R'} = 1 if $opts{'r'};
-
 	$self->{options} = { map { defined $_ ? $_ : 0 } %opts };
 	$self->{files}   = $self->{args};