the 1st post would do it if you always only have two keys, if an unknown number of keys can be given try this...

#!/usr/bin/perl
use strict;
use warnings;


my $usr_str = "{depTar}{name}";
my @keys    = $usr_str =~ m/\{(.*?)\}/g;

my $xml  = { 'depTar' => { 'name' => 'c_p20', 'loc' => 'srvr1' }};
my $href = $xml;

for my $i (0 .. $#keys) {
       $href = $href->{$keys[$i]};
};

print $href;
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