Quote strings containing [ or ] when saving an alsa config

Signed-off-by: Bert Marcelis <bert.marcelis@outlook.com>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

src/conf.c

@@ -1531,6 +1531,8 @@ static void string_print(char *str, int id, snd_output_t *out)
 	case '.':
 	case '{':
 	case '}':
+	case '[':
+	case ']':
 	case '\'':
 	case '"':
 		goto quoted;