Add the BIND_ALLOW_FREEZE flag to NLS bindings

This will result in the NLS process not getting the CPU_TIME capability
solely because the binding exists. The process will get the capability
granted only while it is processing any binder calls on the bound
service.

Flag: com.android.server.notification.allow_freezing_idle_nls

Test: atest FrameworksUiServicesNotificationTests:\
NotificationListenersTest

Bug: 344050265
Change-Id: Ie6f77368774d17c2ab91b0e822dcf547fcb4b7e7