hammerhead: update prebuilt kernel

cfd2308 net: wireless: bcmdhd: check packet length for event messages

Bug: 25306181
Bug: 25668859

Linux version 3.4.0-gcfd2308 (android-build@wped27.hot.corp.google.com)
(gcc version 4.8 (GCC) ) #1 SMP PREEMPT Thu Dec 10 06:33:24 UTC 2015

Change-Id: Icb9eed40851f20e1646990be5c41caca2dbee3d7
Signed-off-by: Patrick Tjin <pattjin@google.com>
diff --git a/zImage-dtb b/zImage-dtb
index bb5735a..1a58f3f 100644
--- a/zImage-dtb
+++ b/zImage-dtb
Binary files differ