cmake: Fix find_library for ubusd and examples/server

Both ubusd and cli TARGET_LINK_LIBRARIES reference ${json} which is
obtained via find_library(), but since the find_library() is searched
after the TARGET_LINK_LIBRARIES for ubusd, ubusd always gets an empty
${json} variable.

examples/server also links against libjson-c, but we were not setting
TARGET_LINK_LIBRARIES accordingly, so do that too with ${json} appended.

This was causing linking errors for ubusd and then examples/server using
an external toolchain (stbgcc-4.8-1.x).

Fixes: 9f52d1769b762 ("cli: use the new json-c library name")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>

CMakeLists.txt

@@ -32,10 +32,11 @@ INCLUDE_DIRECTORIES(${ubox_include_dir})
 ADD_LIBRARY(ubus SHARED libubus.c libubus-io.c libubus-obj.c libubus-sub.c libubus-req.c libubus-acl.c)
 TARGET_LINK_LIBRARIES(ubus ${ubox_library})
 
+find_library(json NAMES json-c json)
+
 ADD_EXECUTABLE(ubusd ubusd.c ubusd_id.c ubusd_obj.c ubusd_proto.c ubusd_event.c ubusd_acl.c ubusd_monitor.c)
 TARGET_LINK_LIBRARIES(ubusd ${ubox_library} ${blob_library} ${json})
 
-find_library(json NAMES json-c json)
 ADD_EXECUTABLE(cli cli.c)
 SET_TARGET_PROPERTIES(cli PROPERTIES OUTPUT_NAME ubus)
 TARGET_LINK_LIBRARIES(cli ubus ${ubox_library} ${blob_library} ${json})

examples/CMakeLists.txt

@@ -5,7 +5,7 @@ INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}/..)
 
 IF (BUILD_EXAMPLES)
 	ADD_EXECUTABLE(server server.c count.c)
-	TARGET_LINK_LIBRARIES(server ubus ${ubox_library} ${blob_library})
+	TARGET_LINK_LIBRARIES(server ubus ${ubox_library} ${blob_library} ${json})
 
 	ADD_EXECUTABLE(client client.c count.c)
 	TARGET_LINK_LIBRARIES(client ubus ${ubox_library})