vector: Introduce shrink() function to shrink vector size without loosing data.
vector: Introduce shrink() function to shrink vector size without loosing data.

Change-Id: I9c0ac2715aea1a90c9e6ebcd982522b80a547099

ttsou/osmo-trx,ttsou/osmo-trx,osmocom/osmo-trx,osmocom/osmo-trx,ttsou/osmo-trx,osmocom/osmo-trx,osmocom/osmo-trx,ttsou/osmo-trx