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: If5499e11d872e629a018fc77d5adf5d0cb863d48

.gitignore

@@ -72,3 +72,5 @@ doc/manuals/generated/
 doc/manuals/osmomsc-usermanual.xml
 doc/manuals/common
 doc/manuals/build
+
+contrib/osmo-msc.spec

configure.ac

@@ -267,4 +267,5 @@ AC_OUTPUT(
     doc/sequence_charts/Makefile
     contrib/Makefile
     contrib/systemd/Makefile
+    contrib/osmo-msc.spec
     Makefile)

contrib/osmo-msc.spec.in

@@ -12,27 +12,26 @@
 # 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/
-#
-
 ## Disable LTO for now since it breaks compilation of the tests
 ## https://osmocom.org/issues/4115
 %define _lto_cflags %{nil}
 
-
 %define with_iu 1
 Name:           osmo-msc
-Version:        1.6.1.32
+Version:        @VERSION@
 Release:        0
 Summary:        Osmocom's MSC for 2G and 3G circuit-switched mobile networks
 License:        AGPL-3.0-or-later AND GPL-2.0-only
 Group:          Productivity/Telephony/Servers
-URL:            https://osmocom.org/projects/osmomsc/wiki
+URL:            https://osmocom.org/projects/osmomsc
 Source:         %{name}-%{version}.tar.xz
 BuildRequires:  autoconf
 BuildRequires:  automake
 BuildRequires:  libdbi-drivers-dbd-sqlite3
 BuildRequires:  libtool
+%if 0%{?suse_version}
+BuildRequires:  systemd-rpm-macros
+%endif
 BuildRequires:  pkgconfig >= 0.20
 BuildRequires:  pkgconfig(dbi)
 BuildRequires:  pkgconfig(libcrypto) >= 0.9.5
@@ -86,6 +85,7 @@ make %{?_smp_mflags}
 %install
 %make_install
 
+%if 0%{?suse_version}
 %preun
 %service_del_preun %{name}.service
 
@@ -97,6 +97,7 @@ make %{?_smp_mflags}
 
 %post
 %service_add_post %{name}.service
+%endif
 
 %check
 make %{?_smp_mflags} check || (find . -name testsuite.log -exec cat {} +)