am 155a70b9: am de9db8f7: am fa36875d: Merge "Make strerror(3) and strsignal(3) thread-safe, and add psignal(3) and psiginfo(3)."

* commit '155a70b93fcccf8e5dec108fb730e25471eaecba':
  Make strerror(3) and strsignal(3) thread-safe, and add psignal(3) and psiginfo(3).