Without this patch, if acl was build beforehand, the build could find
the library resulting in a non-deterministic build.
Sadly there is no --disable or --without option available so this
approach is the only mechanism available.
(From OE-Core rev: 629e0702161886f1fad9552ce451ed2b7dc77967)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>