clisp: turn off optimization

Fixes some build issues on Lion.

Apparently it's enough to remove just the '-O' flags and preserve our
other optimization flags. This may only be needed on Lion, but frankly
clisp tends to have issues on all platforms so it's probably acceptable
to just disable it everywhere.

Closes Homebrew/homebrew#10450.

Signed-off-by: Jack Nagel <jacknagel@gmail.com>

Formula/clisp.rb

@@ -20,6 +20,7 @@ class Clisp < Formula
 
   def install
     ENV.j1 # This build isn't parallel safe.
+    ENV.remove_from_cflags /-O./
 
     # Clisp requires to select word size explicitly this way,
     # set it in CFLAGS won't work.