- `m4/ax_lib_readline.m4` was already aware of "$with_readline".
Move the entire handling of the parameter inside the AX_LIB_READLINE
macro.
This lets our fork of ax_lib_readline.m4 further deviate from upstream
version, but it's already so different that this is no new problem.
- raise an error if the user requested --with-readline=libreadline|libedit
but the library was not found.
- only allow yes|no for --with-nmcli argument. But still default to
"yes", which will always require one libreadline library to be
detected. In particular, don't automatically disable nmcli if
libreadline is not available, because building without nmcli
should be an explicit choice. That is like before.
- update the "$with_readline" variable for the "auto" case to reflect
what was detected.
bf86f51c9e