Silence gcc longjmp warnings:

Silence gcc longjmp warnings:
* prompter.c (krb5_prompter_posix): Make ointrfunc, fd, and errcode volatile.
* promptusr.c (krb5_os_get_tty_uio): Make ointrfunc and retval volatile.
* read_pwd.c (krb5_read_password): Make ointrfunc volatile.  Fix volatile decl
for readin_string (pointer is volatile, doesn't point to volatile).

* changepw.c (krb5_change_password): Wait only two minutes, not indefinitely,
for a response from the kpasswd server.

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@11873 dc483132-0cff-0310-8789-dd5450dbe970