[wpiutil] Vendor llvm and update to 13.0.0 (#4224)

wpiutil/src/test/native/cpp/json/unit-cbor.cpp

@@ -35,6 +35,9 @@ SOFTWARE.
 #include "gtest/gtest.h"
 
 #include "unit-json.h"
+
+#include <cmath>
+
 using wpi::json;
 
 #include <fstream>

wpiutil/src/test/native/cpp/json/unit-constructor1.cpp

@@ -35,6 +35,7 @@ SOFTWARE.
 #include "gtest/gtest.h"
 
 #include <array>
+#include <cmath>
 #include <deque>
 #include <forward_list>
 #include <list>

wpiutil/src/test/native/cpp/json/unit-conversions.cpp

@@ -38,6 +38,7 @@ SOFTWARE.
 using wpi::json;
 using wpi::JsonTest;
 
+#include <cmath>
 #include <deque>
 //#include <forward_list>
 #include <list>

wpiutil/src/test/native/cpp/json/unit-element_access2.cpp

@@ -35,6 +35,9 @@ SOFTWARE.
 #include "gtest/gtest.h"
 
 #include "unit-json.h"
+
+#include <cmath>
+
 using wpi::json;
 
 class JsonElementObjectAccessTestBase {

wpiutil/src/test/native/cpp/json/unit-msgpack.cpp

@@ -37,6 +37,7 @@ SOFTWARE.
 #include "unit-json.h"
 using wpi::json;
 
+#include <cmath>
 #include <fstream>
 
 TEST(MessagePackDiscardedTest, Case)

wpiutil/src/test/native/cpp/json/unit-pointer_access.cpp

@@ -35,6 +35,9 @@ SOFTWARE.
 #include "gtest/gtest.h"
 
 #include "unit-json.h"
+
+#include <cmath>
+
 using wpi::json;
 
 TEST(JsonPointerTest, TypesCreate)