Dump the per-thread TAGGED_ADDR_CTRL value if available.

This value indicates whether memory tagging is enabled on a thread,
the mode (sync or async) and the set of excluded tags. This information
can sometimes be important for understanding an MTE related crash,
so include it in the per-thread tombstone output.

Bug: 135772972
Change-Id: I25a16e10ac7fbb2b1ab2a961a5279f787039000b
diff --git a/debuggerd/debuggerd_test.cpp b/debuggerd/debuggerd_test.cpp
index 108787e..5ed9e57 100644
--- a/debuggerd/debuggerd_test.cpp
+++ b/debuggerd/debuggerd_test.cpp
@@ -309,6 +309,11 @@
   std::string result;
   ConsumeFd(std::move(output_fd), &result);
   ASSERT_MATCH(result, R"(signal 11 \(SIGSEGV\), code 1 \(SEGV_MAPERR\), fault addr 0xdead)");
+
+  if (mte_supported()) {
+    // Test that the default TAGGED_ADDR_CTRL value is set.
+    ASSERT_MATCH(result, R"(tagged_addr_ctrl: 000000000007fff3)");
+  }
 }
 
 TEST_F(CrasherTest, tagged_fault_addr) {