constify to_info_proc and friends

constify to_info_proc and friends

This makes a parameter of to_info_proc const and then fixes up some
fallout, including parameters in a couple of gdbarch methods.

I could not test the procfs.c change.  I verified it by inspection.
If this causes an error here, it will be trivial to fix.

2014-06-16  Tom Tromey  <tromey@redhat.com>

	* target.h (struct target_ops) <to_info_proc>: Make parameter
	const.
	(target_info_proc): Update.
	* target.c (target_info_proc): Make "args" const.
	* procfs.c (procfs_info_proc): Update.
	* linux-tdep.c (linux_info_proc): Update.
	(linux_core_info_proc_mappings): Make "args" const.
	(linux_core_info_proc): Update.
	* gdbarch.sh (info_proc, core_info_proc): Make "args" const.
	* gdbarch.c: Rebuild.
	* gdbarch.h: Rebuild.
	* corelow.c (core_info_proc): Update.