remove world read/write permissions from /dev/diag

/dev/diag has world read/write permissions which is considered
a security risk. Remove these permissions.

Add qcom_diag group for relevant processes. Access to diag requires
processes to be part of a new "qcom_diag" group. Adding qmuxd to be
part of this new group to be able to log messages to diag.

Change-Id: Id7b12958320dd1ed303ebb527621e16f42086e08
bluez: start dbus for BT services on encrypted device

On restart of the Android framework after the user enters
the correct password for decrypting an encrypted phone,
dbus service which is required by Bluetooth services
also needs to be started.

Also combine the trigger actions into the same group
for this framework restart stage.

Change-Id: I13a42ed54519d982f2541a33afc73f9591af2a55