Formatting changes.

Formatting changes.
(obstack_grow, obstack_grow0): Don't cast WHERE at all: that would
prevent type checking.
(obstack_ptr_grow, obstack_ptr_grow_fast): When assigning, don't
cast the value to (void *): assigning a `foo *' to a `void *'
variable is valid.
(obstack_int_grow, obstack_int_grow_fast): Don't cast AINT to int.