systemc: Allow specific functions to shadow the base class method

systemc: Allow specific functions to shadow the base class method

sc_in::bind and sc_core::sc_object::print shadow their respective base
class method. This change adds the necessary declarations to inform
the compiler that this is intentional.

Change-Id: I8c6bc0f05aa568630783db63d52be90f4ea4748c
Signed-off-by: Nikos Nikoleris <nikos.nikoleris@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/c/15135
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>