Require GNU awk at ./configure time.
Some components (specifically {,e}glibc) will not build when awk
is not GNU awk. Make ./configure check for GNU awk.
1 This is NOT the official version of dialog. This version has been
2 significantly modified from the original. It is for use by the Linux
3 kernel configuration script. Please do not bother Savio Lam with
4 questions about this program.