capnp: add --without-shared option.
capnp: add 0.4.1 bottle.

Closes #33620.

Signed-off-by: Mike McQuaid <mike@mikemcquaid.com>
capnp: general cleanup.
ocaml 4.02.1: make X11 optional by default

This disables the little-used Graphics module by default, but leaves
it installable via a `--with-x11` option in the package.
+camlp4 4.02.1+1
opam: add camlp4 to the recommended list

Since OCaml 4.02.0, camlp4 is distributed separately from the main
compiler distribution.  However, it is still required to be installed
alongside the system compiler for the majority of packages.

See #33596 for more discussion on this topic.
opam: bump revision to account for 9c96882a2c1395b7a9ebc411f9f087ebfb3b052
camlp4: add missing version, and add testcase
ocaml: remove duplicated depends_on x11
camlp4: add 4.02.1+1 bottle.
objective-caml: update 4.02.1_1 bottle.
opam: update 1.2.0_1 bottle.