[PATCH] time: Use struct alloc_buffer in __tzfile_read

[Paul Eggert]

Florian Weimer wrote:
> +  if (alloc_buffer_alloc_array (&buf, __time64_t, num_transitions)
> +      != transitions)
> +    /* Either the start of the allocation moved unexpectedly
> +       (misaligned heap pointer, should not happen), or we had an
> +       overflow.  */
> +    goto lose;

Is this comparison needed? The overflow will be caught later anyway, and the != 
comparison cannot fail.

Otherwise it looks good; thanks.