This patch implements various atomic and locking routines on RISC-V. We
mandate the A extension on Linux-capable RISC-V systems, so this can
rely on always having the various atomic instructions availiable.
2018-01-29 Palmer Dabbelt <palmer@sifive.com>
* sysdeps/riscv/nptl/bits/pthreadtypes-arch.h: New file.
* sysdeps/riscv/nptl/bits/semaphore.h: Likewise.
* sysdeps/riscv/nptl/libc-lowlevellock.c: Likewise.
* sysdeps/unix/sysv/linux/riscv/atomic-machine.h: Likewise.
