Rename cond "bootstrap" as "menhir".

The reason for this is that it causes the final package to be named
ocaml-dune-2.5.1-2.fc33~bootstrap.  This breaks build automation since
fedpkg verrel returns the name without the ~bootstrap appendage.

ocaml-dune.spec

@@ -2,11 +2,11 @@
 
 # Since menhir now requires dune to build, but dune needs menhir only for the
 # tests, build in bootstrap mode to skip the tests and the need for menhir.
-%bcond_without bootstrap
+%bcond_without menhir
 
 Name:           ocaml-%{libname}
 Version:        2.5.1
-Release:        2%{?dist}
+Release:        3%{?dist}
 Summary:        A composable build system for OCaml
 
 # Dune itself is MIT.  Some bundled libraries have a different license:
@@ -28,7 +28,7 @@ BuildRequires:  ocaml-findlib
 BuildRequires:  python3dist(sphinx)
 BuildRequires:  python3dist(sphinx-rtd-theme)
 
-%if %{without bootstrap}
+%if %{without menhir}
 # Required by tests.
 BuildRequires:  ocaml-menhir
 %endif
@@ -125,7 +125,7 @@ rm -fr %{buildroot}%{_prefix}/doc
 mkdir -p %{buildroot}%{_pkgdocdir}/
 cp -ar README.md CHANGES.md MIGRATION.md doc/_build/* %{buildroot}%{_pkgdocdir}/
 
-%if %{without bootstrap}
+%if %{without menhir}
 %check
 # These are the only tests we can run.  The others require components that
 # either depend on dune themselves or are not available in Fedora at all.
@@ -190,8 +190,9 @@ cp -ar README.md CHANGES.md MIGRATION.md doc/_build/* %{buildroot}%{_pkgdocdir}/
 %{_emacs_sitelispdir}/dune*
 
 %changelog
-* Tue Apr 21 2020 Richard W.M. Jones <rjones@redhat.com> - 2.5.1-2
+* Tue Apr 21 2020 Richard W.M. Jones <rjones@redhat.com> - 2.5.1-3
 - OCaml 4.11.0 pre-release attempt 2
+- Rename cond "bootstrap" as "menhir".
 
 * Sun Apr 19 2020 Jerry James <loganjerry@gmail.com> - 2.5.1-1
 - New version 2.5.1