Counters: remove need for "slot" by incrementing base pointer.
Counters: enable faster counters with --enable-rdtscp.

We were missing an AC_DEFINE() to ensure the setting in config.h.
Net: remove inline from printf helper.

This wont always be inlined anyway due to size, so no real need to
worry about it. We can simplify things with -Bsymbolic in library
situations anyway.