* include/signal.h: No libc_hidden_proto for raise,
__libc_current_sigrtmin, __libc_current_sigrtmax.
These need to be overridden by linuxthreads.
* sysdeps/posix/raise.c: Reverted.
* sysdeps/generic/raise.c: Reverted.
* signal/allocrtsig.c: Reverted.