ucm: add cfg-save command

Allow to save whole (or partial) local UCM alsa library configuration
to a file.

Syntax (saves key1.key2 sub-tree):

	Sequence [
		cfg-save "/tmp/my-file.conf:key1.key2"
	]

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

src/ucm/utils.c

@@ -512,6 +512,9 @@ void uc_mgr_free_sequence_element(struct sequence_element *seq)
 	case SEQUENCE_ELEMENT_TYPE_SHELL:
 		free(seq->data.exec);
 		break;
+	case SEQUENCE_ELEMENT_TYPE_CFGSAVE:
+		free(seq->data.cfgsave);
+		break;
 	default:
 		break;
 	}