unix: update Dockerfile to go 1.9.2

Update go to 1.9.2 in the Dockerfile used to generate the Linux go files.

The update also changes some zerror definitions: RLIM_INFINITY is
assigned to Rlimit.{Cur,Max} which are both uint64 on all architectures.
PR_SET_PTRACER_ANY is used with Prctl which expects an uintptr.

With the current version, an "constant -1 overflows uint64" error would
result if these constants were used directly without type conversion.

Change-Id: Iefd23a44e983b4fcf210121776531df225014112
Reviewed-on: https://go-review.googlesource.com/73873
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/unix/zerrors_linux_mipsle.go b/unix/zerrors_linux_mipsle.go
index dc7e101..f795862 100644
--- a/unix/zerrors_linux_mipsle.go
+++ b/unix/zerrors_linux_mipsle.go
@@ -1279,7 +1279,7 @@
 	RLIMIT_RTTIME                        = 0xf
 	RLIMIT_SIGPENDING                    = 0xb
 	RLIMIT_STACK                         = 0x3
-	RLIM_INFINITY                        = -0x1
+	RLIM_INFINITY                        = 0xffffffffffffffff
 	RTAX_ADVMSS                          = 0x8
 	RTAX_CC_ALGO                         = 0x10
 	RTAX_CWND                            = 0x7