ci: build.sh: Add a wrapper function over meson's setup

The reason for this wrapper is that all job functions introduced in
future patches will refer to this one instead of open-coding the same
'meson setup' invocation N times. It also prevents 'setup' to be called
multiple times as some future job functions might actually do just that
in a transitive manner.

Signed-off-by: Erik Skultety <eskultet@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>

ci/build.sh

@@ -32,3 +32,8 @@ run_cmd() {
     printf "\e[32m[RUN COMMAND]: '%s'\e[0m\n" "$*"
     "$@"
 }
+
+run_meson_setup() {
+    run_cmd meson setup build --error -Dsystem=true $MESON_OPTS $MESON_ARGS || \
+    (cat "${GIT_ROOT}/build/meson-logs/meson-log.txt" && exit 1)
+}