This patch move the single-thread syscall optimization defintions from
syscall-cancel.h to new header file single-thread.h and also move the
cancellation definitions from pthreadP.h to syscall-cancel.h.
The idea is just simplify the inclusion of both syscall-cancel.h and
single-thread.h (without the requirement of including all pthreadP.h
defintions).
No semantic changes expected, checked on a build for all major ABIs.
* nptl/pthreadP.h (CANCEL_ASYNC, CANCEL_RESET, LIBC_CANCEL_ASYNC,
LIBC_CANCEL_RESET, __libc_enable_asynccancel,
__libc_disable_asynccancel, __librt_enable_asynccancel,
__libc_disable_asynccancel, __librt_enable_asynccancel,
__librt_disable_asynccancel): Move to ...
* sysdeps/unix/sysv/linux/sysdep-cancel.h: ... here.
(SINGLE_THREAD_P, RTLD_SINGLE_THREAD_P): Move to ...
* sysdeps/unix/sysv/linux/single-thread.h: ... here.
* sysdeps/generic/single-thread.h: New file.
* sysdeps/unix/sysdep.h: Include single-thread.h.
* sysdeps/unix/sysv/linux/futex-internal.h: Include sysdep-cancel.h.
* sysdeps/unix/sysv/linux/lowlevellock-futex.h: Likewise.
