vhacd: Reapply downstream changes to namespace conflicting bullet code

Also adding a patch to easily identify and reapply them.

thirdparty/vhacd/src/btConvexHullComputer.cpp

@@ -49,6 +49,10 @@ typedef unsigned long long int32_t uint64_t;
 #include <stdio.h>
 #endif
 
+// -- GODOT start --
+namespace VHACD {
+// -- GODOT end --
+
 // Convex hull implementation based on Preparata and Hong
 // Ole Kniemeyer, MAXON Computer GmbH
 class btConvexHullInternal {
@@ -2477,3 +2481,7 @@ btScalar btConvexHullComputer::compute(const void* coords, bool doubleCoords, in
 
     return shift;
 }
+
+// -- GODOT start --
+}; // namespace VHACD
+// -- GODOT end --