Fix incompatbility with C++20

C++20 introduced stricter rules for aggregate initialization: a class or
struct is no longer an aggregate if its constructor is explicitly
defaulted. Define an explicit constructor taking parameters to handle
aggregate initializations in existing code when compiled with C++20.

Change-Id: If0eb78812d4241c870a14f1f4c2ba79c732ff265
Signed-off-by: Limin <limintang@gmail.com>