bug#14196: Problem with invoking "missing" in directory with "(" in name (Automake 1.11.6, Autoconf 2.68

[Karl Berry]

    + MISSING="\${SHELL} '$am_aux_dir/missing'" ;;

I made this change. Two tests (man6 and am-missing-prog) that were
grepping for the path to missing needed adjusting for the quotes being
present now.

Closing this one. Thanks all. -k