Fix build with rust-toolset

RHEL/ELN rust-toolset is currently disparate from Fedora rust-packaging.
While we are working on bringing them in sync, right now we need to
handle the current state so that this builds.

bootc.spec

@@ -21,7 +21,7 @@ Source1:        %{url}/releases/download/v%{version}/bootc-%{version}-vendor.tar
 BuildRequires: make
 BuildRequires: ostree-devel
 BuildRequires: openssl-devel
-%if 0%{?rhel} && !0%{?eln}
+%if 0%{?rhel}
 BuildRequires: rust-toolset
 %else
 BuildRequires: cargo-rpm-macros >= 25
@@ -38,13 +38,19 @@ Recommends: bootupd
 
 %prep
 %autosetup -p1 -a1
+%if 0%{?rhel}
+%cargo_prep -V 1
+%else
 %cargo_prep -v vendor
+%endif
 
 %build
 %cargo_build
+%if !0%{?rhel}
 %cargo_vendor_manifest
 %cargo_license_summary
 %{cargo_license} > LICENSE.dependencies
+%endif
 
 %install
 %make_install INSTALL="install -p -c"
@@ -57,8 +63,10 @@ Recommends: bootupd
 %files
 %license LICENSE-MIT
 %license LICENSE-APACHE
+%if !0%{?rhel}
 %license LICENSE.dependencies
 %license cargo-vendor.txt
+%endif
 %doc README.md
 %{_bindir}/bootc
 %{_prefix}/lib/bootc/