Suppress lint warnings on google-default-arguments

The lint rule google-default-arguments ensures that virtual or override
methods do not have default arguments, because different default values
across the hierarchy chain (e.g. Base::foo(int a=0) v.s.
Derived::foo(int a=10)) can cause confusions.

However, since the uses of the default arguments in libbinder don't lead
to such problem, suppress the warnings.

Test: WITH_TIDY=true WITH_TIDY_CHECKS=google-default-arguments m
libbinder does not show any warning about google-default-arguments

Change-Id: Ica41034ab0ad1037a0facc447ee47e0c77fa9c55