libproto: Fix memset problem noticed by gcc 4.8.1

Signed-off-by: Ben Greear <greearb@candelatech.com>
random:  Fix unused variable warning in gcc 4.8.1

Signed-off-by: Ben Greear <greearb@candelatech.com>
policy:  Fix compile warnings in lex source files.

The gcc 4.8.1 compiler complains about this, possibly
related to dodgy lex on Fedora 19.
lex:  Work around lex bugs on Fedora 19.

This disables sign mismatch warnings in the compiler so we can
compile 'clean' on Fedora 19 with lex bug:

https://bugzilla.redhat.com/show_bug.cgi?id=993447

Signed-off-by: Ben Greear <greearb@candelatech.com>