binder: initialize lsm_context structure

It is possible to reach the end of binder_transaction() without
having set lsmctx. As the variable value is checked there it needs
to be initialized.

Suggested-by: Kees Bakker <[e-mail]>
[PM: subj tweak to fit convention]
Signed-off-by: Casey Schaufler <[e-mail]>
Signed-off-by: Paul Moore <[e-mail]>

drivers/android/binder.c

···
 	struct binder_context *context = proc->context;
 	int t_debug_id = atomic_inc_return(&binder_last_id);
 	ktime_t t_start_time = ktime_get();
-	struct lsm_context lsmctx;
+	struct lsm_context lsmctx = { };
 	struct list_head sgc_head;
 	struct list_head pf_head;
 	const void __user *user_buffer = (const void __user *)