Use vendored dependencies in RHEL builds

RHEL does not package individual Rust dependencies.

.gitignore

@@ -3,3 +3,4 @@
 /virtiofsd-1.4.0.crate
 /virtiofsd-1.5.0.crate
 /virtiofsd-1.5.1.crate
+/virtiofsd-1.5.1-vendor.tar.xz

sources

@@ -1 +1,2 @@
 SHA512 (virtiofsd-1.5.1.crate) = e8a4aaaa6084b5c111333fff738ed8082cd114098dbf4ff42f48192449e899e64fc406de3872adc8e8d82c7a4f9730989e691c80f85ddabb2441908be8460873
+SHA512 (virtiofsd-1.5.1-vendor.tar.xz) = 3a1eecdd70283d003232be0e335f044236554e8155354f7debd69b7e0387dd39b4d1da22ae967bb0e8fcf920a58f023f7a5461f7637855a715ea0ebd1b51f35b

virtiofsd.spec

@@ -7,13 +7,20 @@ Summary:        Virtio-fs vhost-user device daemon (Rust version)
 License:        ASL 2.0 and BSD
 URL:            https://gitlab.com/virtio-fs/virtiofsd
 Source:         %{crates_source}
-Patch:          virtiofsd-relax-env_logger-dep.diff
+# To create the vendor tarball:
+#   tar xf %%{name}-%%{version}.crate ; pushd %%{name}-%%{version} ; \
+#   cargo vendor && tar Jcvf ../%%{name}-%%{version}-vendor.tar.xz vendor/ ; popd
+Source1:        %{name}-%{version}-vendor.tar.xz
 
 ExclusiveArch:  %{rust_arches}
 # Some of our deps (i.e. vm-memory) are not available on 32 bits targets.
 ExcludeArch:    i686
 
+%if 0%{?rhel}
+BuildRequires:  rust-toolset
+%else
 BuildRequires:  rust-packaging >= 21
+%endif
 BuildRequires:  libcap-ng-devel
 BuildRequires:  libseccomp-devel
 Requires:       qemu-common
@@ -29,10 +36,14 @@ Provides:       qemu-virtiofsd = 2:7.2.1-1
 
 %prep
 %autosetup -n %{name}-%{version_no_tilde} -p1
+%if 0%{?rhel}
+%cargo_prep -V 1
+%else
 %cargo_prep
 
 %generate_buildrequires
 %cargo_generate_buildrequires
+%endif
 
 %build
 %cargo_build