[wpiutil] timestamp: Call FPGA functions directly (#5235)

This works around an exit race with wpi::Now() on Rio; it was overridden
to call HAL_GetFPGATime(), which calls chipobject, but on exit, because
there was not a library dependency, the chipobject could be destroyed
prior to wpiutil/wpinet being shut down.

ntcore/src/test/native/cpp/main.cpp

@@ -4,10 +4,13 @@
 
 #include <climits>
 
+#include <wpi/timestamp.h>
+
 #include "gmock/gmock.h"
 #include "ntcore.h"
 
 int main(int argc, char** argv) {
+  wpi::impl::SetupNowRio();
   nt::AddLogger(nt::GetDefaultInstance(), 0, UINT_MAX, [](auto& event) {
     if (auto msg = event.GetLogMessage()) {
       std::fputs(msg->message.c_str(), stderr);