* intervals.c (temp_set_point, temp_set_point_both): Use EMACS_INT.

* intervals.c (temp_set_point, temp_set_point_both): Use EMACS_INT.
(set_point, set_point_both): Use EMACS_INT.  Remove `buffer' arg,
work on current_buffer only instead (that was already the case
for some of the code anyway).
* buffer.h (set_point, set_point_both): Remove buffer arg, use long int.
(temp_set_point, temp_set_point_both): Use EMACS_INT.
(SET_PT, SET_PT_BOTH): Adjust.
* intervals.h (set_point, temp_set_point, set_point_both)
(temp_set_point_both): Remove redundant declarations.