I did not find in configure.in where SYSTEM_LIBS where set for other...

I did not find in configure.in where SYSTEM_LIBS where set for other platforms, and why I did not have required extra libraries added in sdl-config, so I set it there

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%401551

configure.in

@@ -2306,6 +2306,8 @@ case "$target" in
             fi
             have_timers=yes
         fi
+        # Now set libraries needed in sdl-config
+        SYSTEM_LIBS="$EXTRA_LDFLAGS"
         ;;
     *-riscos)
         ARCH=riscos