Bluetooth: Fix for BT grey out

In ATM test when BT fails to turn on and enable timeout occurs
bluetooth manager service tries to recover from error and restarts
enable process. Meanwhile stack  tries to enable BT due to preload
wait timout. Due towhich ref count gets incremented twices and the
manager service enable process fails due to connection refused for
userial open.As ref count is incremented by 2 sucessive turn on fails
and BT greys out.To fix the issue enable timeout is increased to 12
sec as preload timeout is 5sec and preload retry is two times.

Change-Id: If3878fcccb8c0e2c2db3acd4f3907b78884fcb8a
CRs-fixed: 671991