Fix null deref and uaf in mach0 parser
static int inSymtab(SdbHash *hash, struct symbol_t *symbols, const char *name, ut64 addr) {
	bool found;
	const char *key = sdb_fmt (0, "%s.%"PFMT64x, name, addr);
	(void)sdb_ht_find (hash, key, &found);
	if (found) {
		return true;
	}
	sdb_ht_insert (hash, key, "1");
	return false;
}

static int inSymtab(SdbHash *hash, struct symbol_t *symbols, const char *name, ut64 addr) {
	bool found;
	const char *key = sdb_fmt (0, "%s.%"PFMT64x, name, addr);
	(void)sdb_ht_find (hash, key, &found);
	if (found) {
		return true;
	}
	sdb_ht_insert (hash, key, "1");
	return false;
}
