lib{c,lzma,z}: remove -DSYMBOL_VERSIONING from CFLAGS

This was part of a libkse and libpthread transition aide when libc
gained symbol versions in e62165c8b0f7d6452c0033127a0fd8ad1d9e34d3
(March 2006). The code that cared about this macro was removed in
commit 00fb440c1a145b56b6c75fd405d80071aef2aab1 (May 2007) when symbol
versioning was enabled by default and libthr became the default
threading library. For unknown reasons, it stayed in libc (which
seemingly never used it) and seems to have been copied to liblzma and
libz.

Reviewed by: imp, kib, emaste
Differential Revision: https://reviews.freebsd.org/D42613

(cherry picked from commit e3e9c205ff54aac287309e03a808d9e9ec5c49eb)