Add script for fetching BTS-specific L1 headers

Several of the supported BTS models require hw-specific L1 headers for
compilation which are stored in separate repository. Instead of
copy-pasting code which obtains those header for each BTS it's better to
create separate script.

Change-Id: I840533d5bf9233822bc0534a25c252f1cab0a7b0
Related: SYS#3682

scripts/osmo-layer1-headers.sh

@@ -0,0 +1,47 @@
+#!/bin/sh
+
+# -e: fail if any of the subsequent commands fail
+# -x: trace each executed command via debug log
+set -e -x
+
+# Usage:
+# ./osmo-layer1-headers.sh sysmo superfemto_v5.1
+# where 'sysmo' is BTS type and 'superfemto_v5.1' is version specifier (tag or branch for git reset)
+# 2nd parameter is optional and defaults to latest master branch
+
+case "$1" in
+    sysmo)
+	uri="git://git.sysmocom.de/sysmo-bts/layer1-api"
+	version="origin/master"
+	;;
+    oct)
+	uri="git://git.osmocom.org/octphy-2g-headers"
+	version="origin/master"
+	;;
+    lc15)
+	uri="https://gitlab.com/nrw_litecell15/litecell15-fw"
+	version="nrw/litecell15-next"
+	;;
+    *)
+	echo "Unknown BTS model '$1'"
+	exit 1
+	;;
+esac
+
+# if 2nd parameter was specified and it's not 'master' then use it instead of default
+if [ -n "$2" ]
+then
+    if [ "$2" != "master" ]
+    then
+	version=$2
+    fi
+fi
+
+if ! test -d layer1-headers;
+then
+    git clone "$uri" layer1-headers
+fi
+
+cd layer1-headers
+git fetch origin
+git reset --hard "$version"