Add a new error code LIB_ERR_SYSTEM_CALL to the ferr subsystem.
Additionally convert LIB_ERR_VRF_SOCKET to a more generic
LIB_ERR_SOCKET.
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>
Add code to auto-create the ferr infrastructure as well as add
some initial error handling for vrf.c
Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>