contrib/jenkins.sh: add new script

Prepare to replace the legacy SIMTRACE jenkins job with a new
master-simtrace job that works like other master build jobs. Move the
build commands from the old job into this contrib/jenkins.sh file.

contrib/jenkins.sh

@@ -0,0 +1,23 @@
+#!/bin/sh -e
+TOPDIR="$(realpath "$(dirname "$0")/..")"
+
+if ! [ -x "$(command -v osmo-build-dep.sh)" ]; then
+	echo "Error: missing scripts from osmo-ci.git in PATH!"
+	exit 2
+fi
+
+set -x
+
+osmo-clean-workspace.sh
+
+export deps="$TOPDIR/deps"
+export inst="$deps/install"
+export PKG_CONFIG_PATH="$inst/lib/pkgconfig:$PKG_CONFIG_PATH"
+export LD_LIBRARY_PATH="$inst/lib"
+
+mkdir -p deps
+osmo-build-dep.sh libosmocore "" '--disable-doxygen'
+
+cd "$TOPDIR"/host
+$MAKE clean
+$MAKE