Use %{?rhel} macros in spec

Backport of https://build.opensuse.org/request/show/1123605

contrib/osc.spec

@@ -15,15 +15,15 @@
 # need to override python_sitelib because it is not set as we would expect on many distros
 %define python_sitelib %(RPM_BUILD_ROOT= %{use_python} -Ic "import sysconfig; print(sysconfig.get_path('purelib'))")
 
-# generate manpages on distros where argparse-manpage >= 3 is available
-%if 0%{?suse_version} > 1500 || 0%{?fedora} >= 37
+# generate manpages on distros where argparse-manpage >= 3 and python3-Sphinx are available
+%if 0%{?suse_version} > 1500 || 0%{?fedora} >= 37 || 0%{?rhel} >= 9
 %bcond_without man
 %else
 %bcond_with man
 %endif
 
 # whether to use fdupes to deduplicate python bytecode
-%if 0%{?suse_version} || 0%{?fedora}
+%if 0%{?suse_version} || 0%{?fedora} || 0%{?rhel} >= 8
 %bcond_without fdupes
 %else
 %bcond_with fdupes
@@ -33,7 +33,7 @@
 %define obs_build_pkg obs-build
 %define sphinx_pkg %{use_python_pkg}-Sphinx
 
-%if 0%{?fedora}
+%if 0%{?fedora} || 0%{?rhel} >= 9
 %define argparse_manpage_pkg argparse-manpage
 %define sphinx_pkg %{use_python_pkg}-sphinx
 %endif
@@ -110,7 +110,7 @@ Recommends:     obs-service-source_validator
 Recommends:     obs-service-tar_scm
 Recommends:     obs-service-verify_file
 
-%if 0%{?fedora}
+%if 0%{?fedora} || 0%{?rhel}
 Recommends:     openssh
 %endif
 %if 0%{?suse_version}