Add support for new architecture loongarch (#1173)

src/cycleclock.h

@@ -173,6 +173,10 @@ inline BENCHMARK_ALWAYS_INLINE int64_t Now() {
   struct timeval tv;
   gettimeofday(&tv, nullptr);
   return static_cast<int64_t>(tv.tv_sec) * 1000000 + tv.tv_usec;
+#elif defined(__loongarch__)
+  struct timeval tv;
+  gettimeofday(&tv, nullptr);
+  return static_cast<int64_t>(tv.tv_sec) * 1000000 + tv.tv_usec;
 #elif defined(__s390__)  // Covers both s390 and s390x.
   // Return the CPU clock.
   uint64_t tsc;