typeck: support implicit bit vector types
typeck: support implicit bit vector types

Support bit vector types with implicit type, i.e. `localparam [31:0]`.
Simply assume that a packed array of an implicit type will always map to
a bit or logic.

fabianschuiki/moore,fabianschuiki/moore,fabianschuiki/moore,fabianschuiki/moore,fabianschuiki/moore