debuggerd: fix missed use of ptrace(PTRACE_ATTACH). am: 8b6b654a5f
am: fe59793375

Change-Id: I22b74c49b17eeb17c46891e4404a2ca8c562bea7
diff --git a/debuggerd/tombstone.cpp b/debuggerd/tombstone.cpp
index aeffc66..d04b721 100644
--- a/debuggerd/tombstone.cpp
+++ b/debuggerd/tombstone.cpp
@@ -447,7 +447,7 @@
     }
 
     // Skip this thread if cannot ptrace it
-    if (ptrace(PTRACE_ATTACH, new_tid, 0, 0) < 0) {
+    if (!ptrace_attach_thread(pid, new_tid)) {
       _LOG(log, logtype::ERROR, "ptrace attach to %d failed: %s\n", new_tid, strerror(errno));
       continue;
     }