reporting full subdir path for subconfigure

[Karl Berry]

It's certainly not a critical issue, but in configuring a complex source
tree (TeX Live), I would sometimes find it useful to be told up front
exactly what directory is being subconfigured.  So, I wonder about
changing this line in status.m4:

    AC_MSG_NOTICE([configuring in $ac_dir])

to something showing the full path, say:

    AC_MSG_NOTICE([configuring in $ac_dir ($srcdir/$ac_dir)])

Would that be considered harmful by anyone?

Thanks,
Karl