tbf_dl: comment why we sent a dummy LLC packets to delay the release of the TBF

Change-Id: I1862674437dffef4de3ffa7b183ecf690020b0ec
Reviewed-on: https://gerrit.osmocom.org/143
Reviewed-by: Harald Welte <laforge@gnumonks.org>
Tested-by: Jenkins Builder
1 file changed