VOL-1497 : Add more control to kv/memory access

- Added kv locking mechanism (etcd only)
- (watch) control path access whenever possible
- (watch) use a transaction for updates and merge with memory
- cleaned up vendoring
- misc changes to fix exceptions found along the way

Amendments:

- Copyright header got removed in auto-generated file
- Changed default locking to false for KV list operation
- Updated backend api to allow the passing of locking parameter

Change-Id: Ie1a55d3ca8b9d92ae71a85ce42bb22fcf1419e2c
diff --git a/vendor/golang.org/x/sys/unix/syscall_linux.go b/vendor/golang.org/x/sys/unix/syscall_linux.go
index e371445..4bb86aa 100644
--- a/vendor/golang.org/x/sys/unix/syscall_linux.go
+++ b/vendor/golang.org/x/sys/unix/syscall_linux.go
@@ -14,6 +14,7 @@
 import (
 	"encoding/binary"
 	"net"
+	"runtime"
 	"syscall"
 	"unsafe"
 )
@@ -80,6 +81,12 @@
 	return ioctl(fd, req, uintptr(unsafe.Pointer(value)))
 }
 
+func IoctlSetRTCTime(fd int, value *RTCTime) error {
+	err := ioctl(fd, RTC_SET_TIME, uintptr(unsafe.Pointer(value)))
+	runtime.KeepAlive(value)
+	return err
+}
+
 // IoctlGetInt performs an ioctl operation which gets an integer value
 // from fd, using the specified request number.
 func IoctlGetInt(fd int, req uint) (int, error) {
@@ -100,6 +107,12 @@
 	return &value, err
 }
 
+func IoctlGetRTCTime(fd int) (*RTCTime, error) {
+	var value RTCTime
+	err := ioctl(fd, RTC_RD_TIME, uintptr(unsafe.Pointer(&value)))
+	return &value, err
+}
+
 //sys	Linkat(olddirfd int, oldpath string, newdirfd int, newpath string, flags int) (err error)
 
 func Link(oldpath string, newpath string) (err error) {
@@ -981,6 +994,20 @@
 	return setsockopt(fd, level, opt, unsafe.Pointer(mreq), unsafe.Sizeof(*mreq))
 }
 
+// SetsockoptSockFprog attaches a classic BPF or an extended BPF program to a
+// socket to filter incoming packets.  See 'man 7 socket' for usage information.
+func SetsockoptSockFprog(fd, level, opt int, fprog *SockFprog) error {
+	return setsockopt(fd, level, opt, unsafe.Pointer(fprog), unsafe.Sizeof(*fprog))
+}
+
+func SetsockoptCanRawFilter(fd, level, opt int, filter []CanFilter) error {
+	var p unsafe.Pointer
+	if len(filter) > 0 {
+		p = unsafe.Pointer(&filter[0])
+	}
+	return setsockopt(fd, level, opt, p, uintptr(len(filter)*SizeofCanFilter))
+}
+
 // Keyctl Commands (http://man7.org/linux/man-pages/man2/keyctl.2.html)
 
 // KeyctlInt calls keyctl commands in which each argument is an int.
@@ -1442,7 +1469,6 @@
 //sys	Pselect(nfd int, r *FdSet, w *FdSet, e *FdSet, timeout *Timespec, sigmask *Sigset_t) (n int, err error) = SYS_PSELECT6
 //sys	read(fd int, p []byte) (n int, err error)
 //sys	Removexattr(path string, attr string) (err error)
-//sys	Renameat(olddirfd int, oldpath string, newdirfd int, newpath string) (err error)
 //sys	Renameat2(olddirfd int, oldpath string, newdirfd int, newpath string, flags uint) (err error)
 //sys	RequestKey(keyType string, description string, callback string, destRingid int) (id int, err error)
 //sys	Setdomainname(p []byte) (err error)
@@ -1467,6 +1493,7 @@
 
 //sys	Setpriority(which int, who int, prio int) (err error)
 //sys	Setxattr(path string, attr string, data []byte, flags int) (err error)
+//sys	Signalfd(fd int, mask *Sigset_t, flags int) = SYS_SIGNALFD4
 //sys	Statx(dirfd int, path string, flags int, mask int, stat *Statx_t) (err error)
 //sys	Sync()
 //sys	Syncfs(fd int) (err error)
@@ -1683,7 +1710,6 @@
 // Shmdt
 // Shmget
 // Sigaltstack
-// Signalfd
 // Swapoff
 // Swapon
 // Sysfs