Add nullptr check for AudioManager Framework Component

Summary: Some framework components do not check
whether the system service being called is null or not
causing "FATAL EXCEPTION" in zygote system process.
Adding nullptr or NULL obj check before calling.

Test: m
flash the device
verify the zygote is running stable and not hitting
FATAL EXECEPTION.

Bug: 380022127
Merged-In: I5db3f6b99224c335109e83312fd6bc6252d23392
Change-Id: I866499d723c8630dbf1d711bd55b97cf6308300e
Signed-off-by: Abdelrahman Daim <adaim@meta.com>