Currently `make publish` fails on Jenkins because there is nothing
to publish. In [1] we simply forgot to pass '--enable-manuals'
if $WITH_MANUALS is set to 1, so no PDFs are built. Fix this.
Change-Id: I85dfecf2025a0466fccfe5a1e63cda788f85992e
Fixes: [1] I28353f51de798535a3bb6efdc6c2da443d96ddfb
pcap-config is not present as libpcap is part of the base system.
Use it as /bin/true and inject -lpcap as PCAP_LIBS.
Change-Id: I0c2b5222da0ee037d3a3156ac1fef89dfd849cad