automake: stop supporting "%KEY?iftrue:iffalse%" transforms And the similar "reduced forms" "%KEY:iffalse%" and "%KEY?iftrue%" as well. They are convoluted, never used (after the previous change), and will get in the way in the Automake-NG branch, where we'll soon want to use GNU make static pattern rules in our internal '*.am' fragments. * automake.in (preprocess_file, transform): Simplify not to support those transform patterns. Signed-off-by: Stefano Lattarini <stefano.lattarini@gmail.com>