update vendor directory

vendor/golang.org/x/sys/unix/mkall.sh

@@ -89,6 +89,8 @@ case "$1" in
 -syscalls)
 	for i in zsyscall*go
 	do
+		# Run the command line that appears in the first line
+		# of the generated file to regenerate it.
 		sed 1q $i | sed 's;^// ;;' | sh > _$i && gofmt < _$i > $i
 		rm _$i
 	done
@@ -280,7 +282,7 @@ esac
 			syscall_goos="syscall_bsd.go $syscall_goos"
 			;;
 		esac
-		if [ -n "$mksyscall" ]; then echo "$mksyscall $syscall_goos $GOOSARCH_in |gofmt >zsyscall_$GOOSARCH.go"; fi
+		if [ -n "$mksyscall" ]; then echo "$mksyscall -tags $GOOS,$GOARCH $syscall_goos $GOOSARCH_in |gofmt >zsyscall_$GOOSARCH.go"; fi
 		;;
 	esac
 	if [ -n "$mksysctl" ]; then echo "$mksysctl |gofmt >$zsysctl"; fi