astgen: do not discard result location in for/while loops
If we use the discard result location any break with a value will be
ignored and not checked for usage.
Closes https://github.com/ziglang/zig/issues/14684.
e41bc640c6John Schmidt committed on 3/1/2023, 7:51:59 AM· committed by Andrew Kelleyparent98508a1