kernel UAPI and each architecture with deviate values have their own
implementation (currently only mips).
No semantic change is expected, checked on a build against x86_64-linux-gnu,
alpha-linux-gnu, mips64-linux-gnu, and sparc64-linux-gnu.
* sysdeps/unix/sysv/linux/Makefile (sysdep_headers): Add
termios-tcflow.h.
* sysdeps/unix/sysv/linux/bits/termios-tcflow.h: New file.
* sysdeps/unix/sysv/linux/mips/bits/termios-tcflow.h: Likewise.
* sysdeps/unix/sysv/linux/bits/termios.h (TCSANOW, TCSADRAIN,
TCSAFLUSH): Move to termios-tcflow.h.
* sysdeps/unix/sysv/linux/alpha/bits/termios.h: Likewise.
* sysdeps/unix/sysv/linux/mips/bits/termios.h: Likewise.
* sysdeps/unix/sysv/linux/powerpc/bits/termios.h: Likewise.
* sysdeps/unix/sysv/linux/sparc/bits/termios.h: Likewise.