fix #3037: include the split_list to shell_qoute

Based to the suggestion of Wolfgang, in regard to `split_list()`,
 I converted the `split_list()` to `split(/\0/, $param->{$key});`
 this will split the `$param->{$key}` null characters and push each
 element to the `$args` array along with the key value.

 changes since v1:
 * get rid of the `use PVE::Tools qw(split_list);` since not need it anymore.
 * replace the split_list to split(/\0/).

Signed-off-by: Moayad Almalat <m.almalat@proxmox.com>

PVE/CLI/pvesh.pm

@@ -106,7 +106,7 @@ sub proxy_handler {
     my $args = [];
     foreach my $key (keys %$param) {
 	next if $key eq 'quiet' || $key eq 'output-format'; # just to  be sure
-	push @$args, "--$key", $param->{$key};
+	push @$args, "--$key", $_ for split(/\0/, $param->{$key});
     }
 
     my $remcmd = ['ssh', '-o', 'BatchMode=yes', "root\@$remip",