meson.build: work around Meson error "Dependencies must be external deps"
meson.build: work around Meson error "Dependencies must be external deps"

Happens because stopwatch_dep=[] in the optimized build.

CM4all/beng-proxy,CM4all/beng-proxy,CM4all/beng-proxy,CM4all/beng-proxy,CM4all/beng-proxy,CM4all/beng-proxy