pthread_setconcurrency.3: ATTRIBUTES: Note functions that are thread-safe

The functions pthread_setconcurrency() and
pthread_getconcurrency() are thread safe.

Signed-off-by: Peng Haitao <penght@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
pthread_getcpuclockid.3: ATTRIBUTES: Note function that is thread-safe

The function pthread_getcpuclockid() is thread safe.

Signed-off-by: Peng Haitao <penght@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
pthread_equal.3: ATTRIBUTES: Note function that is thread-safe

The function pthread_equal() is thread safe.

Signed-off-by: Peng Haitao <penght@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
pthread_exit.3: ATTRIBUTES: Note function that is thread-safe

The function pthread_exit() is thread safe.

Signed-off-by: Peng Haitao <penght@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
pthread_setaffinity_np.3: ATTRIBUTES: Note functions that are thread-safe

The functions pthread_setaffinity_np() and
pthread_getaffinity_np() are thread safe.

Signed-off-by: Peng Haitao <penght@cn.fujitsu.com>
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
shmget.2: wfix

The section is about failures, no need to recall this for that
specific error code.

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>