Remove calling signal finalization

Remove calling signal finalization

Sometimes, the app process is deadlock while calling the g_object_unref().
While calling fork(), gdbus thread of the parent process has a mutex
locked. In the child, the mutex is in the locked state.
(locked by a nonexistent thread and thus can never be unlocked.)

Backtrace:
 - #0  0xb6132900 in syscall () from /usr/lib/libc-2.24.so
 - #1  0xb63aab90 in g_mutex_lock_slowpath () from /usr/lib/libglib-2.0.so.0.5200.2
 - #2  0xb635bbe4 in g_source_destroy_internal () from /usr/lib/libglib-2.0.so.0.5200.2
 - #3  0xb657f510 in _g_kdbus_worker_stop () from /usr/lib/libgio-2.0.so.0.5200.2
 - #4  0xb65365d4 in g_dbus_connection_dispose () from /usr/lib/libgio-2.0.so.0.5200.2
 - #5  0xb6434720 in g_object_unref () from /usr/lib/libgobject-2.0.so.0.5200.2
 - #6  0x004e1361 in _signal_fini () from /usr/bin/launchpad-process-pool
 - #7  0x004dac9d in __exec_app_process () from /usr/bin/launchpad-process-pool
 - #8  0x004d9f0f in __fork_app_process () from /usr/bin/launchpad-process-pool
 - #9  0x004dc01b in __handle_launch_event () from /usr/bin/launchpad-process-pool

Change-Id: Iaad316621111f2494381f440c3a7fe0ab4473731
Signed-off-by: Hwankyu Jhun <h.jhun@samsung.com>