Fix hardcoded link flag to "dl" library

Fix "dlopen" function detection
(cherry picked from commit c73ca85a76)

CMakeLists.txt

@@ -78,6 +78,10 @@ set( DL_LIBRARIES dl )
 check_library_exists( ${DL_LIBRARIES} dlopen /lib HAVE_LIBDL )
 if( NOT HAVE_LIBDL )
   unset( DL_LIBRARIES )
+  check_function_exists( dlopen HAVE_DLOPEN )
+  if( HAVE_DLOPEN )
+    set( HAVE_LIBDL 1 )
+  endif( HAVE_DLOPEN )
 endif( NOT HAVE_LIBDL )
 
 find_package( Threads )
@@ -87,7 +91,7 @@ find_package( Threads )
 include( CheckFunctionExists )
 
 set( bak_CMAKE_REQUIRED_LIBRARIES ${CMAKE_REQUIRED_LIBRARIES} )
-set( CMAKE_REQUIRED_LIBRARIES dl )
+set( CMAKE_REQUIRED_LIBRARIES ${DL_LIBRARIES} )
 check_function_exists( dlerror HAVE_DLERROR )
 check_function_exists( strcmp HAVE_STRCMP )
 check_function_exists( strchr HAVE_STRCHR )

artsc/CMakeLists.txt

@@ -65,7 +65,7 @@ install( FILES
 tde_add_library( artsdsp SHARED
   SOURCES artsdsp.c
   VERSION 0.0.0
-  LINK artsc-shared dl
+  LINK artsc-shared ${DL_LIBRARIES}
   DESTINATION ${LIB_INSTALL_DIR}
 )