func_curl: Fix leak of an ast_str in error handling code path.

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Merged revisions 360413 from http://svn.asterisk.org/svn/asterisk/branches/1.8


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/10@360414 65c4cc65-6c06-0410-ace0-fbb531ad65f3

funcs/func_curl.c

@@ -608,6 +608,7 @@ static int acf_curl_helper(struct ast_channel *chan, const char *cmd, char *info
 
 	if (!(curl = ast_threadstorage_get(&curl_instance, sizeof(*curl)))) {
 		ast_log(LOG_ERROR, "Cannot allocate curl structure\n");
+		ast_free(str);
 		return -1;
 	}