[PATCH] Call the right helper function when setting mallopt M_ARENA_MAX

[Florian Weimer]

* Wladimir J. van der Laan:

> Fixes a typo introduced in commit
> be7991c0705e35b4d70a419d117addcd6c627319. This caused
> mallopt(M_ARENA_MAX) as well as the environment variable
> MALLOC_ARENA_MAX to not work as intended because it set the
> wrong internal parameter.
>
> 	* malloc/malloc.c: Call do_set_arena_max for M_ARENA_MAX
> 	instead of incorrect do_set_arena_test

Patch looks good, but I think this warrants a bug report and reference
to it in the ChangeLog.