1.91.0: Boost.Predef checks are no longer installed

It looks like https://github.com/boostorg/boost/pull/1118 have broken installation of [Boost.Predef checks](https://github.com/boostorg/predef/blob/a2a5010e2824b7740890a3bf463b8c4b8927aaa7/build.jam#L41-L43) when installing Boost.

Here's a full build log:

[ubuntu-noble-broken.log](https://github.com/user-attachments/files/27025997/ubuntu-noble-broken.log)

The command line used to install Boost is:

```
/build/boost/boost/b2 -j16 -q -d2 --layout=system --ignore-site-config --user-config=/build/boost/boost/user-config.jam variant=release debug-symbols=on cxxstd=23-gnu numa=on --prefix=/build/boost/boost/debian/tmp/usr \
--libdir=/build/boost/boost/debian/tmp/usr/lib/x86_64-linux-gnu \
--without-python link=static,shared install
```

which is at line 42366 in the attached log.

Normally, you would see installation into `/build/boost/boost/debian/tmp/usr/share/boost_predef` after b2 finishes its configuring work.

Reverting https://github.com/boostorg/boost/pull/1118 fixes this.

CC @grisumbras