Don't include the headers for dynamically loading the VP library if NO_DYNAMIC_VP is defined

bundleloader.h, which is included if MACOS is defined, defines
inline functions that reference bundle loading system functions,
which requires linking to the core foundation framework.

Avoid requiring linking to extra libraries/frameworks if
NO_DYNAMIC_VP is defined.

codec/encoder/core/src/wels_preprocess.cpp

@@ -30,6 +30,7 @@
  *
  */
 
+#ifndef NO_DYNAMIC_VP
 #if defined(_WIN32)
 #include <windows.h>
 #elif defined(MACOS)
@@ -37,6 +38,7 @@
 #elif defined(__GNUC__)
 #include <dlfcn.h>
 #endif
+#endif
 
 #include <stdio.h>
 #include <stdlib.h>