* malloc/malloc.c (bin_at): Rewrite to be more clear and to not

* malloc/malloc.c (bin_at): Rewrite to be more clear and to not

	waste bins[0..1].
	(malloc_state): Reduce bins size by 2.
	(_int_malloc): Fix test for large enough buffer for early termination.
	When no unsorted block matches perfectly and an exiting block has
	to be split, use full list insert and not shortcut which assumes
	the list is empty.