go.sys/windows: apply latest syscall changes

71db3dc120af os: make SameFile handle paths like c:a.txt properly
ff34a3e84dc0 net: fix CNAME resolving on Windows

LGTM=r
R=golang-codereviews, r
CC=golang-codereviews
https://golang.org/cl/130250043
diff --git a/windows/zsyscall_windows.go b/windows/zsyscall_windows.go
index 69f0e37..e6a7662 100644
--- a/windows/zsyscall_windows.go
+++ b/windows/zsyscall_windows.go
@@ -140,6 +140,7 @@
 	procgetprotobyname                     = modws2_32.NewProc("getprotobyname")
 	procDnsQuery_W                         = moddnsapi.NewProc("DnsQuery_W")
 	procDnsRecordListFree                  = moddnsapi.NewProc("DnsRecordListFree")
+	procDnsNameCompare_W                   = moddnsapi.NewProc("DnsNameCompare_W")
 	procGetAddrInfoW                       = modws2_32.NewProc("GetAddrInfoW")
 	procFreeAddrInfoW                      = modws2_32.NewProc("FreeAddrInfoW")
 	procGetIfEntry                         = modiphlpapi.NewProc("GetIfEntry")
@@ -1635,6 +1636,12 @@
 	return
 }
 
+func DnsNameCompare(name1 *uint16, name2 *uint16) (same bool) {
+	r0, _, _ := syscall.Syscall(procDnsNameCompare_W.Addr(), 2, uintptr(unsafe.Pointer(name1)), uintptr(unsafe.Pointer(name2)), 0)
+	same = r0 != 0
+	return
+}
+
 func GetAddrInfoW(nodename *uint16, servicename *uint16, hints *AddrinfoW, result **AddrinfoW) (sockerr error) {
 	r0, _, _ := syscall.Syscall6(procGetAddrInfoW.Addr(), 4, uintptr(unsafe.Pointer(nodename)), uintptr(unsafe.Pointer(servicename)), uintptr(unsafe.Pointer(hints)), uintptr(unsafe.Pointer(result)), 0, 0)
 	if r0 != 0 {