delete public and shared tables

Public and shared tables are deleted when the ebpf program that created
them is deleted.  If other programs are using such table, it remains
until it is deleted.

Signed-off-by: Mauricio Vasquez B <mauriciovasquezbernal@gmail.com>

src/cc/bpf_module.cc

@@ -152,7 +152,16 @@ BPFModule::~BPFModule() {
 
   if (btf_)
     delete btf_;
+  auto it = ts_->lower_bound(Path({id_}));
+  while (it != ts_->upper_bound(Path({id_}))) {
+    // try to delete public and shared tables that are mine
+    if (it->second.is_shared && !it->second.is_extern) {
+      ts_->Delete(Path({maps_ns_, it->second.name}));
+    }
+    it++;
+  }
 
+  // delete all local tables
   ts_->DeletePrefix(Path({id_}));
 }