As noted in bug 20126, MIPS n64 uses an incorrect implementation of
readahead intended for 32-bit systems. This patch adds a
syscalls.list entry to fix this. An updated version of the
consolidation patch
<https://sourceware.org/ml/libc-alpha/2016-09/msg00527.html> could
remove this syscalls.list entry again.
Tested with compilation (only) for mips64; the nature of the syscall
doesn't allow for a glibc test to detect this issue.
[BZ #21026]
* sysdeps/unix/sysv/linux/mips/mips64/n64/syscalls.list
(readahead): New syscall entry.