netd: Enable clang-tidy and fix all warnings

Bug: 65246407
Test: m netd && system/netd/tests/runtests.sh
Change-Id: I1d22b2bc317fe7218ccde78859ed0623d6a1f8df
diff --git a/server/XfrmController.cpp b/server/XfrmController.cpp
index e229cf8..59500f9 100644
--- a/server/XfrmController.cpp
+++ b/server/XfrmController.cpp
@@ -182,7 +182,7 @@
 }
 
 // returns the address family, placing the string in the provided buffer
-StatusOr<uint16_t> convertStringAddress(std::string addr, uint8_t* buffer) {
+StatusOr<uint16_t> convertStringAddress(const std::string& addr, uint8_t* buffer) {
     if (inet_pton(AF_INET, addr.c_str(), buffer) == 1) {
         return AF_INET;
     } else if (inet_pton(AF_INET6, addr.c_str(), buffer) == 1) {