[serialization_lib] Add TosaSerializationOpInfo

Add TosaSerializationOpInfo<Op> to op.h
and use it in test_serialization_unit.cpp to make sure it
is working correctly.

Signed-off-by: Tai Ly <tai.ly@arm.com>
Change-Id: I9cd08a20f929cbd2bba5754749e1300eb5c28a3e