nptl: fix use of IS_IN_LIBPTHREAD macro
nptl: fix use of IS_IN_LIBPTHREAD macro

IS_IN_LIBPTHREAD should be IS_IN_libpthread instead.

Signed-off-by: Carmelo Amoroso <532378793705a04edd56deb76ad8c0442834d55d@st.com>

joel-porquet/tsar-uclibc,joel-porquet/tsar-uclibc,joel-porquet/tsar-uclibc,joel-porquet/tsar-uclibc