[RFA] enum enable

[Jim Blandy]

> 2001-07-14  Eli Zaretskii  <eliz@is.elta.co.il>
> 
> 	The following changes avoid polluting global namespace with the
> 	`enable' and `disable' identifiers, because some platforms define
> 	in their system headers symbols with global scope that go by those
> 	names.
> 

Why are the following changes necessary?  Structure members aren't in
the global namespace:

> 	(struct breakpoint): Rename the `enable' member to `enable_state'.
> 	(args_for_catchpoint_enable): Rename the `enable' member to
> 	`enable_p'.  All users changed.
> 	(struct tracepoint): The member `enabled' is now `int enabled_p'.
> 	* printcmd.c (struct display): The `status' member is now an int.
> 	* memattr.h (struct mem_region): Rename the `status' member to
> 	`enabled_p'.