[libc][NFC] Use `#include <math.h>` in utils/FPUtil/ManipulationFunctions.h.

This reverts commit 352cba2441c6c4e00f067c9c68358cc0a6a5fffb.
"add back math.h #include utils/FPUtil/ManipulationFunctions.h".

Using `<math.h>` correct so downstream setup should be fixed.

GitOrigin-RevId: 2d9ae1d217890639518252ee1f39c9cc759749ef
diff --git a/utils/FPUtil/ManipulationFunctions.h b/utils/FPUtil/ManipulationFunctions.h
index 2bac1b5..79dc741 100644
--- a/utils/FPUtil/ManipulationFunctions.h
+++ b/utils/FPUtil/ManipulationFunctions.h
@@ -13,10 +13,10 @@
 #include "NearestIntegerOperations.h"
 #include "NormalFloat.h"
 
-#include "include/math.h"
 #include "utils/CPP/TypeTraits.h"
 
 #include <limits.h>
+#include <math.h>
 
 namespace __llvm_libc {
 namespace fputil {