cln: remove useless bits

[ryandesign (Ryan Carsten Schmidt)]

The cln port has some useless parts that should be removed. See the attached patch.

• The platform darwin 7 part is useless because MacPorts itself can no longer be installed on darwin 7 or earlier.
• The test variant is useless because the test phase is not run unless the user requests it explicitly using "sudo port test cln". Nothing is gained by setting the test variables in a variant; just set them unconditionally.
• The --with-gmp configure arg is useless because cln finds gmp just fine on its own, and anyway the location specified was wrong and fills the log with things like "ld: warning: directory '/opt/local/lib/lib' following -L not found".
• The --infodir configure args are useless because cln already knows where to put its info file.
• The --mandir configure arg is useless because cln doesn't install any man pages, and even if it did, cln's configure script appears to already know the correct location for man pages.

[ryandesign (Ryan Carsten Schmidt)]

proposed patch

[ryandesign (Ryan Carsten Schmidt)]

Committed in r68021 (maintainer timeout).