Revert "test: skip `alternative constraints` behavior test on LoongArch"

This reverts commit f90548e74063cd1d6ac6885ee9f6521359cde8cf.

The bug was fixed in LLVM 22.
d6dd695b82Alex Rønne Petersen committed on 2/19/2026, 6:14:07 PMparent35b5a4f
1 file changedLine totals unavailable