Fix AUTO keyword not giving variable asignment restrictions

[errgrab]

When you assign variables using the auto keyword you don't have any of variable assignment restrictions.
Example:

int	main(void)
{
	auto int a = 0, b = 1;
	auto int c = 0, d = 1;
	auto int e = 0, f = 1;
}

[malallai]

Can you please add tests for this ? Thank you !