Fixed bug 3807 - Remove restriction from DECLSPEC macro for OS/2

Ozkan Sezer

The following patch removes the unnecessary / wrong
Watcom restriction from the DECLSPEC macro for OS/2.

include/begin_code.h

@@ -61,7 +61,7 @@
 #  else
 #   define DECLSPEC __declspec(dllexport)
 #  endif
-# elif defined(__OS2__) && defined(__WATCOMC__)
+# elif defined(__OS2__)
 #   ifdef BUILD_SDL
 #    define DECLSPEC    __declspec(dllexport)
 #   else