ubus: update to version 2019-12-19

Contains following changes:

 a1523d76b016 fix blob parsing vulnerability by using blob_parse_untrusted
 c60583743ccf ubus_monitor: workaround possibly false positive uses of memory after it is freed
 dac6c7c575ac ubusd_monitor: fix possible null pointer dereference
 060dfbb26da3 ubus_common: remove duplicate ARRAY_SIZE and add missing include
 c5f2053dfcfd workaround possibly false positive uses of memory after it is freed
 72be8e93f07d lua: ubus_lua_do_subscribe: fix copy&paste error
 a995b1e68129 lua: workaround false positive dereference of null pointer
 08f17c87a000 add fuzzer and cram based unit tests
 c413be9b376c refactor ubusd.c into reusable ubusd_library
 afd47189e864 examples: remove dead increments
 b2e544238672 add initial GitLab CI support
 058f4e9526ed libubus: fix incompatible pointer types assigment
 d2e026a33df8 iron out all extra compiler warnings
 5d7ca8309d0a ubusd/libubus-io: fix variable sized struct position warning
 d61282db5640 ubusd: fix comparison of integers of different signs
 90fb16234c22 cmake: enable extra compiler checks

and bumps ABI_VERSION to 20191219.

Signed-off-by: Petr Štetiar <ynezz@true.cz>

package/system/ubus/Makefile

@@ -5,9 +5,9 @@ PKG_RELEASE:=1
 
 PKG_SOURCE_PROTO:=git
 PKG_SOURCE_URL=$(PROJECT_GIT)/project/ubus.git
-PKG_SOURCE_DATE:=2018-10-06
-PKG_SOURCE_VERSION:=221ce7e7ff1bd1a0c9995fa9d32f58e865f7207f
-PKG_MIRROR_HASH:=e6ab3f009688740eb6d7a1857df59a6ba10ae8ae0fac78ae0fd6672f71c02dce
+PKG_SOURCE_DATE:=2019-12-19
+PKG_SOURCE_VERSION:=a1523d76b016ed46501f61e38ad38999d6c66f52
+PKG_MIRROR_HASH:=f0d46cac85d60e24e3f835c729ee17bb29f0e75c8bd831a86fb3456debd9ad62
 CMAKE_INSTALL:=1
 
 PKG_LICENSE:=LGPL-2.1
@@ -36,7 +36,7 @@ define Package/libubus
   SECTION:=libs
   CATEGORY:=Libraries
   DEPENDS:=+libubox
-  ABI_VERSION:=20170705
+  ABI_VERSION:=20191219
   TITLE:=OpenWrt RPC client library
 endef