[lldb] Distinguish DWARF binary type-check error messages (#209644)
CheckScalarOperandsHaveSameType reported every operand-check failure
with the same "requires operands to have the same type" message, even
though it rejects operands for three different reasons: mismatched type
kind, mismatched size, and mismatched signedness. That made a failed
check hard to diagnose from the error alone.
Parameterize the message so each check names what actually differs
(type, size, or signedness).
Follow-up to Augusto's review of #209641.