#3757 configure script doesn't honor some --without-foo flags

[Michael Orlitzky]

The ./configure script for Maxima announces the usual GNUisms:

Optional Packages:
  --with-PACKAGE[=ARG]    use PACKAGE [ARG=yes]
  --without-PACKAGE       do not use PACKAGE (same as --with-PACKAGE=no)
  ...
  --with-ccl=<prog>            Use OpenMCL executable <prog> (default ccl)
  --with-ccl64=<prog>          Use ccl64 executable <prog> (default dx86cl64)

Passing --without-foo doesn't work in some cases though. I noticed this with ccl64, where the resulting value of --with-ccl64=no is interpreted literally as the name of the compiler:

$ ./configure --without-ccl64
...
Summary:
Compiling an maxima image that uses "no"
Use --enable-ccl64-exec to build a standalone executable instead.
default lisp: ccl64
wish executable name: "wish"