Use SLIBSUF instead of .so, as a more generic dynamic library suffix.

Originally committed as revision 25321 to svn://svn.ffmpeg.org/ffmpeg/trunk

configure

@@ -3223,6 +3223,7 @@ cat > $TMPH <<EOF
 #define ASMALIGN(ZEROBITS) ".p2align " #ZEROBITS "\\n\\t"
 #define EXTERN_PREFIX "${extern_prefix}"
 #define EXTERN_ASM ${extern_prefix}
+#define SLIBSUF "$SLIBSUF"
 EOF
 
 test -n "$malloc_prefix" &&

libavfilter/vf_frei0r.c

@@ -192,7 +192,7 @@ static void *load_path(AVFilterContext *ctx, const char *prefix, const char *nam
 {
     char path[1024];
 
-    snprintf(path, sizeof(path), "%s%s.so", prefix, name);
+    snprintf(path, sizeof(path), "%s%s%s", prefix, name, SLIBSUF);
     av_log(ctx, AV_LOG_DEBUG, "Looking for frei0r effect in '%s'\n", path);
     return dlopen(path, RTLD_NOW|RTLD_LOCAL);
 }