[source] ubus: update to the latest version

[LEDE Commits]

nbd pushed a commit to source.git, branch master:
https://git.lede-project.org/2bc647e015d3877735fb4526a4f8f9c594b0a0fc

commit 2bc647e015d3877735fb4526a4f8f9c594b0a0fc
Author: Felix Fietkau <nbd at nbd.name>
AuthorDate: Fri Jan 20 11:34:26 2017 +0100

    ubus: update to the latest version
    
    - Adds support for passing file descriptors in ubus invoke requests
    - Fixes clearing pending timers on ubus_shutdown()
    - Fixes checking the amount of written data in ubusd
    - Fixes an ubusd crash when trying to subscribe to system objects
    
    Signed-off-by: Felix Fietkau <nbd at nbd.name>
---
 package/system/ubus/Makefile | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/package/system/ubus/Makefile b/package/system/ubus/Makefile
index fadb436..218e2d0 100644
--- a/package/system/ubus/Makefile
+++ b/package/system/ubus/Makefile
@@ -5,9 +5,9 @@ PKG_RELEASE:=1
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL=$(LEDE_GIT)/project/ubus.git
-PKG_SOURCE_DATE:=2016-10-12
-PKG_SOURCE_VERSION:=312448a5b147c221836827a7a641e76a4514db44
-PKG_MIRROR_HASH:=adeeae238deaac2b6af77c2e4473febdcbc0f1c256734b2ff019c76b2f3f2aa6
+PKG_SOURCE_DATE:=2017-01-19
+PKG_SOURCE_VERSION:=97ac89f9727d4fae1b2d63d2fc3b59e0d5d4bf65
+PKG_MIRROR_HASH:=1dc6afd3baedc1cc6f4373a34b6d73975358e9741c647b358b4fdd5a72a07756
 CMAKE_INSTALL:=1
 
 PKG_LICENSE:=LGPL-2.1