Fix mosquitto.h header lookup during build time

Author: RunsFor

mqtt/CMakeLists.txt

@@ -20,6 +20,7 @@ add_library(driver SHARED driver.c)
 if( DEFINED STATIC_BUILD )
 	unset(CMAKE_C_FLAGS)
 	add_subdirectory(../third_party/mosquitto ../third_party/mosquitto/build)
+	include_directories(../third_party/mosquitto/lib)
 	if( STATIC_BUILD )
 		target_link_libraries(driver libmosquitto_static ${LDFLAGS_EX})
 	else()