Changes

server: Rename osmo_pcap_server_close_trace -> osmo_pcap_conn_close_trace

Change-Id: I261c6a54bd31b8f511cb103840323e7343bfdc61

Rename osmo_pcap_server_close_conn -> osmo_pcap_conn_close

While at it, remove unnecessary helper function close_connection().

Change-Id: I116f0c4d61d391faa30760be3afdf189ff921d0c

server: Split network code into its own file

Separate code related to network socket handling into its own separate
file, as already done in osmo-pcap-client.
This allows easily finding out which code is operating on the socket and
which code is operating on the pcap file being locally stored.
This will make modifying subsystems easier too.

Change-Id: I41d6e0398605becbea109a7bb5aac8981d65ab1b

server: Avoid lseek syscall on every packet write to pcap file

Instead of requesting the current size to the OS, keep track of the
amount of bytes stored in conn->wr_offset, and check agains that value
when we want to write new data to the file.
This should remove quite a lot of oeverhead when lots of traffic is
being handled.

Change-Id: I437eaca982d65d0f06e7d24863875f85267f0e44

cosmetic: osmo_tls: Fix indentation whitespace

Change-Id: I27e6d6ce64178384acbd0b8ee88d6f7ef6b2a61b

server: Move osmo_pcap_server_alloc() to osmo_server_core.c

Change-Id: I5456e66820cec5bd5acf3cb732b47c42dae7a21e