Fix build with pupnp >= 1.14.13

Rename EXPORT_SPEC to UPNP_EXPORT_SPEC to avoid the following build
failure with pupnp >= 1.14.13 and
pupnp/pupnp@2f99af2:

In file included from src/threadutil/FreeList.h:43,
                 from src/threadutil/TimerThread.h:39,
                 from src/gatedevice.h:32,
                 from src/gatedevice.c:38:
src/threadutil/ithread.h:917:12: error: expected ';' before 'int'
  917 | EXPORT_SPEC int pthread_mutexattr_setkind_np(
      |            ^~~~
      |            ;

Fixes:
 - http://autobuild.buildroot.org/results/2eebf8264327bd492ee8cadc0c539d42c4f2e252

Signed-off-by: Fabrice Fontaine <fabrice.fontaine@orange.com>

linuxigd2/src/threadutil/ThreadPool.h

@@ -41,7 +41,7 @@
 #include "ithread.h"
 #include "LinkedList.h"
 #include "UpnpInet.h"
-#include "UpnpGlobal.h" /* for UPNP_INLINE, EXPORT_SPEC */
+#include "UpnpGlobal.h" /* for UPNP_INLINE, UPNP_EXPORT_SPEC */
 
 #include <errno.h>
 
@@ -505,7 +505,7 @@ int TPAttrSetMaxJobsTotal(
  * \return Always returns 0.
  */
 #ifdef STATS
-	EXPORT_SPEC int ThreadPoolGetStats(
+	UPNP_EXPORT_SPEC int ThreadPoolGetStats(
 		/*! Valid initialized threadpool. */
 		ThreadPool *tp,
 		/*! Valid stats, out parameter. */
@@ -522,7 +522,7 @@ int TPAttrSetMaxJobsTotal(
  * \brief
  */
 #ifdef STATS
-	EXPORT_SPEC void ThreadPoolPrintStats(
+	UPNP_EXPORT_SPEC void ThreadPoolPrintStats(
 		/*! . */
 		ThreadPoolStats *stats);
 #else

linuxigd2/src/threadutil/UpnpGlobal.h

@@ -17,22 +17,22 @@
 
 #ifdef _WIN32
 	/*
-	 * EXPORT_SPEC
+	 * UPNP_EXPORT_SPEC
 	 */
 	#if defined _MSC_VER || defined __BORLANDC__
 		#ifdef UPNP_STATIC_LIB
-			#define EXPORT_SPEC
+			#define UPNP_EXPORT_SPEC
 		#else /* UPNP_STATIC_LIB */
 			#ifdef LIBUPNP_EXPORTS
 				/*! set up declspec for dll export to make functions
 				 * visible to library users */
-				#define EXPORT_SPEC __declspec(dllexport)
+				#define UPNP_EXPORT_SPEC __declspec(dllexport)
 			#else /* LIBUPNP_EXPORTS */
-				#define EXPORT_SPEC __declspec(dllimport)
+				#define UPNP_EXPORT_SPEC __declspec(dllimport)
 			#endif /* LIBUPNP_EXPORTS */
 		#endif /* UPNP_STATIC_LIB */
 	#else /* _MSC_VER || __BORLANDC__ */
-		#define EXPORT_SPEC
+		#define UPNP_EXPORT_SPEC
 	#endif /* _MSC_VER || __BORLANDC__ */
 
 	/*
@@ -88,7 +88,7 @@
 	 * definition upon declaration or it will not be exported on WIN32
 	 * DLLs.
 	 */
-	#define EXPORT_SPEC
+	#define UPNP_EXPORT_SPEC
 
 	/*!
 	 * \brief Declares an inline function.

linuxigd2/src/threadutil/ithread.h

@@ -41,7 +41,7 @@
 	#include <sys/param.h>
 #endif
 
-#include "UpnpGlobal.h" /* For UPNP_INLINE, EXPORT_SPEC */
+#include "UpnpGlobal.h" /* For UPNP_INLINE, UPNP_EXPORT_SPEC */
 #include "UpnpUniStd.h" /* for close() */
 
 #ifdef __cplusplus
@@ -914,7 +914,7 @@ static UPNP_INLINE int ithread_cleanup_thread(void)
 /* !defined(UPNP_USE_MSVCPP) should probably also have pthreads version check -
  * but it's not clear if that is possible */
 /* NK: Added for satisfying the gcc compiler */
-EXPORT_SPEC int pthread_mutexattr_setkind_np(
+UPNP_EXPORT_SPEC int pthread_mutexattr_setkind_np(
 	pthread_mutexattr_t *attr, int kind);
 #endif