Fix implementation of configure check related to TM_IN_SYS_TIME

The logic introduced in commit bfbc549 was incorrect, it should be
inversed to replicate what is in done in autoconf.
See http://git.savannah.gnu.org/gitweb/?p=autoconf.git;a=blob;f=lib/autoconf/types.m4;h=238798eaa84b34c696eb3c5118d04dab20969e27;hb=HEAD#l1023
Add HAVE_BROKEN_PIPE_BUF configure check

Note that I also check in the source of Python 3.3 and the associated
test/check is identical.
See http://hg.python.org/cpython/file/1bf721567067/configure.ac#l4544