[GWP-ASan] Fixed issue with c++ standard library dependency.

Summary:
Removed dependency on c++ standard library. Some supporting allocators (namely Scudo on Fuchsia, and shortly, scudo standalone) has a hard requirement of no c++stdlib.

This patch updates the build system so that we don't have any c++ stdlib dependencies. It also will conveniently fix a racy build-order bug discrepency between GWP-ASan and libc++.

Reviewers: phosek, morehouse

Reviewed By: phosek, morehouse

Subscribers: kubamracek, mgorny, cryptoad, #sanitizers, llvm-commits, beanz, smeenai, vitalybuka

Tags: #sanitizers, #llvm

Differential Revision: https://reviews.llvm.org/D62048

llvm-svn: 360982
GitOrigin-RevId: 364f662fa3f31d262ce5b28065490bc4dceebaac
diff --git a/random.cpp b/random.cpp
index 625973c..67f4a22 100644
--- a/random.cpp
+++ b/random.cpp
@@ -8,7 +8,7 @@
 
 #include "gwp_asan/random.h"
 
-#include <ctime>
+#include <time.h>
 
 namespace gwp_asan {
 uint32_t getRandomUnsigned32() {
diff --git a/random.h b/random.h
index a71f3e5..5fcf30d 100644
--- a/random.h
+++ b/random.h
@@ -9,7 +9,7 @@
 #ifndef GWP_ASAN_RANDOM_H_
 #define GWP_ASAN_RANDOM_H_
 
-#include <cstdint>
+#include <stdint.h>
 
 namespace gwp_asan {
 // xorshift (32-bit output), extremely fast PRNG that uses arithmetic operations