common/l1sap.c: perform noise / ghost filtering for handover RACH
common/l1sap.c: perform noise / ghost filtering for handover RACH

For some reason, the noise / ghost filtering was performed for
normal RACH requests, but not for handover RACH requests. There
are also ghost RACH, interference and noise possible, so let's
extend the filtering coverage.

Change-Id: I94fc15835280d624780200dadc4418210bf565ff

osmocom/osmo-bts,osmocom/osmo-bts,osmocom/osmo-bts