We still need to use this opcode in more places, instead of the generic ldc.i8

We depend on the cprop pass to init local_ref_count. We only add a super instruction if the definition of the an intermediary result is done in the same basic block (the dreg is local var) and it is not used anywhere else, otherwise we can't clear the instruction.

By removing also 2 additional ldloca instructions, and enabling cprop for these vars that no longer have their address taken.