net/http: Improve network configuration routines

Modify the network setup routine to accept the following parameters:
- network context
- accept callback
- server IP address
- server port

This change will allow us to reuse this routine for TLS.

Change-Id: I1fdbaa908783c69f87863cbc597b42f39358762c
Signed-off-by: Flavio Santes <flavio.santes@intel.com>