Make RPM spec compatible with RHEL 6 (#31653)

* Make RPM spec compatible with RHEL 6

* Define __python2 macro only when undefined

(cherry picked from commit 2087dc7384)

packaging/rpm/ansible.spec

@@ -2,7 +2,7 @@
 %define ansible_version $VERSION
 
 %if 0%{?rhel} == 5
-%define __python /usr/bin/python26
+%define __python2 /usr/bin/python26
 %endif
 
 Name:      %{name}
@@ -14,6 +14,7 @@ License:   GPLv3+
 Group:     Development/Libraries
 Source:    http://releases.ansible.com/ansible/%{name}-%{version}.tar.gz
 BuildRoot: %{_tmppath}/%{name}-%{version}-%{release}-buildroot
+%{!?__python2: %global __python2 /usr/bin/python2.6}
 %{!?python_sitelib: %global python_sitelib %(%{__python2} -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())")}
 
 BuildArch: noarch