Revert following commits:

Revert "wake_up_process() should be never used to wakeup a TASK_STOPPED/TRACED task"

This reverts commit 44a4ed9725af7102453c1620c88402b7157a00a2.

Revert "ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL"

This reverts commit a139c164e641ea59868f6198db5dd49646191695.

Revert "ptrace: introduce signal_wake_up_state() and ptrace_signal_wake_up()"

This reverts commit 45fb5832f12ec20e6b257df8a02ccf5183c9c5ee.