build type-info in semantic, not during code-gen
treat types with initializer as "builtin" so the TypeInfo is only generated with the declaration
fine-tune the necessity to semantically process TypeInfo to  avoid regression on simple types
resolve zeroInit in forward referenced struct
calc zeroInit separately
write TypeInfo for typedef with initializer
do not write type info for error type
do not build type info for array literals during CTFE
fix/simplifiy need-semantic check