mod_ladspa: putenv() breaks the process environment variables, use setenv() instead.

Use of putenv() to set LADSPA_PATH broke the proccess environment variables, for some
unknown reason, causing segfaults on "reload mod_ladspa" and restarting
FreeSWITCH (with "fcstl shutdown restart").
Signed-off-by: Stefan Knoblich <s.knoblich@axsentis.de>

src/mod/applications/mod_ladspa/mod_ladspa.c

@@ -627,14 +627,13 @@ SWITCH_MODULE_LOAD_FUNCTION(mod_ladspa_load)
 {
 	switch_application_interface_t *app_interface;
 	switch_api_interface_t *api_interface;
-
 	char *path = getenv("LADSPA_PATH");
 
 	if (zstr(path)) {
 		if (switch_directory_exists("/usr/lib64/ladspa/", pool) == SWITCH_STATUS_SUCCESS) {
-			putenv("LADSPA_PATH=/usr/lib64/ladspa/:/usr/local/lib/ladspa");
+			setenv("LADSPA_PATH", "/usr/lib64/ladspa/:/usr/local/lib/ladspa", 0);
 		} else if (switch_directory_exists("/usr/lib/ladspa/", pool) == SWITCH_STATUS_SUCCESS) {
-			putenv("LADSPA_PATH=/usr/lib/ladspa/:/usr/local/lib/ladspa");
+			setenv("LADSPA_PATH", "/usr/lib/ladspa/:/usr/local/lib/ladspa", 0);
 		}
 	}