dynamic debug: move ddebug_remove_module() down into free_module()

The command

	echo "file ec.c +p" >/sys/kernel/debug/dynamic_debug/control

causes an oops.

Move the call to ddebug_remove_module() down into free_module().  In this
way it should be called from all error paths.  Currently, we are missing
the remove if the module init routine fails.

Signed-off-by: Jason Baron <jbaron@redhat.com>
Reported-by: Thomas Renninger <trenn@suse.de>
Tested-by: Thomas Renninger <trenn@suse.de>
Cc: <stable@kernel.org>		[2.6.32+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>