contrib: integrate RPM spec

Remove OpenSUSE bug report link, set version to @VERSION@, make it build
with CentOS 8 etc.

Related: OS#4550
Change-Id: I387b41b6c524cd3f6baad7e89b4b6b347d9998ac

.gitignore

@@ -33,3 +33,5 @@ doc/manuals/generated/
 doc/manuals/osmomsc-usermanual.xml
 doc/manuals/common
 doc/manuals/build
+
+contrib/osmo-sip-connector.spec

configure.ac

@@ -146,6 +146,7 @@ AC_OUTPUT(
 	doc/manuals/Makefile
 	contrib/Makefile
 	contrib/systemd/Makefile
+	contrib/osmo-sip-connector.spec
 	doc/Makefile
 	doc/examples/Makefile
 	Makefile)

contrib/osmo-sip-connector.spec.in

@@ -12,22 +12,21 @@
 # license that conforms to the Open Source Definition (Version 1.9)
 # published by the Open Source Initiative.
 
-# Please submit bugfixes or comments via http://bugs.opensuse.org/
-#
-
 Name:           osmo-sip-connector
-Version:        1.4.0.0
+Version:        @VERSION@
 Release:        0
 Summary:        MNCC to SIP bridge for osmo-nitb
 License:        AGPL-3.0-or-later AND GPL-2.0-or-later
 Group:          Productivity/Telephony/Servers
-URL:            http://openbsc.osmocom.org/
+URL:            https://osmocom.org/projects/osmo-sip-conector
 Source:         %{name}-%{version}.tar.xz
 BuildRequires:  autoconf
 BuildRequires:  automake
 BuildRequires:  libtool
 BuildRequires:  pkgconfig >= 0.20
+%if 0%{?suse_version}
 BuildRequires:  systemd-rpm-macros
+%endif
 BuildRequires:  pkgconfig(libosmocore) >= 1.0.0
 BuildRequires:  pkgconfig(libosmogsm) >= 1.0.0
 BuildRequires:  pkgconfig(libosmovty) >= 1.0.0
@@ -51,6 +50,7 @@ make %{?_smp_mflags}
 %install
 %make_install
 
+%if 0%{?suse_version}
 %preun
 %service_del_preun %{name}.service
 
@@ -62,6 +62,7 @@ make %{?_smp_mflags}
 
 %post
 %service_add_post %{name}.service
+%endif
 
 %check
 make %{?_smp_mflags} check || (find . -name testsuite.log -exec cat {} +)