Enable clang-tidy for security sensitive domain.

Start with clang-analyzer-security* and cert-*, but disable two
specific errors:

-- cert-err34-c, which checks for atoi(); heavily triggered by
CommandListener, but will disappear when we move to Binder.
-- cert-err58-cpp, which checks for exceptions before main(); it's
a "Low" severity issue, and filed 36656327 to track cleanup.

Fix all other triggered errors along the way.

Test: builds, boots
Bug: 36655947
Change-Id: I1391693fb521ed39700e25ab6b16bc741293bb79
diff --git a/Utils.cpp b/Utils.cpp
index 72d3801..8bdae92 100644
--- a/Utils.cpp
+++ b/Utils.cpp
@@ -292,7 +292,7 @@
         LOG(ERROR) << "Failed to setexeccon";
         abort();
     }
-    FILE* fp = popen(cmd.c_str(), "r");
+    FILE* fp = popen(cmd.c_str(), "r"); // NOLINT
     if (setexeccon(nullptr)) {
         LOG(ERROR) << "Failed to setexeccon";
         abort();