unix: add kernel module load/unload syscalls on Linux

InitModule loads a kernel module from an ELF image. FinitModule loads a
kernel module from a file descriptor. DeleteModule unloads a kernel
module.

These syscalls require the CAP_SYS_MODULE capability.

See http://man7.org/linux/man-pages/man2/init_module.2.html and
http://man7.org/linux/man-pages/man2/delete_module.2.html for details.

Also drop deprecated syscalls related to kernel modules from the list
of unimplemented syscalls.

Change-Id: I131e17f02c5617640f5f4073982d2b27a6d78bbf
Reviewed-on: https://go-review.googlesource.com/c/144173
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

unix/syscall_linux.go

@@ -1304,6 +1304,7 @@ func Mount(source string, target string, fstype string, flags uintptr, data stri
 //sys	ClockGettime(clockid int32, time *Timespec) (err error)
 //sys	Close(fd int) (err error)
 //sys	CopyFileRange(rfd int, roff *int64, wfd int, woff *int64, len int, flags int) (n int, err error)
+//sys	DeleteModule(name string, flags int) (err error)
 //sys	Dup(oldfd int) (fd int, err error)
 //sys	Dup3(oldfd int, newfd int, flags int) (err error)
 //sysnb	EpollCreate1(flag int) (fd int, err error)
@@ -1317,6 +1318,7 @@ func Mount(source string, target string, fstype string, flags uintptr, data stri
 //sys	fcntl(fd int, cmd int, arg int) (val int, err error)
 //sys	Fdatasync(fd int) (err error)
 //sys	Fgetxattr(fd int, attr string, dest []byte) (sz int, err error)
+//sys	FinitModule(fd int, params string, flags int) (err error)
 //sys	Flistxattr(fd int, dest []byte) (sz int, err error)
 //sys	Flock(fd int, how int) (err error)
 //sys	Fremovexattr(fd int, attr string) (err error)
@@ -1338,6 +1340,7 @@ func Getpgrp() (pid int) {
 //sysnb	Getsid(pid int) (sid int, err error)
 //sysnb	Gettid() (tid int)
 //sys	Getxattr(path string, attr string, dest []byte) (sz int, err error)
+//sys	InitModule(moduleImage []byte, params string) (err error)
 //sys	InotifyAddWatch(fd int, pathname string, mask uint32) (watchdesc int, err error)
 //sysnb	InotifyInit1(flags int) (fd int, err error)
 //sysnb	InotifyRmWatch(fd int, watchdesc uint32) (success int, err error)
@@ -1527,8 +1530,6 @@ func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 // ClockNanosleep
 // ClockSettime
 // Clone
-// CreateModule
-// DeleteModule
 // EpollCtlOld
 // EpollPwait
 // EpollWaitOld
@@ -1572,7 +1573,6 @@ func Faccessat(dirfd int, path string, mode uint32, flags int) (err error) {
 // Pselect6
 // Ptrace
 // Putpmsg
-// QueryModule
 // Quotactl
 // Readahead
 // Readv