Type annotations for instruction operands are omitted, e.g.
```
%3 = struct $S(%1, %2)
```
Operand types are redundant anyway and were only used for sanity checking in the SIL parser.
But: operand types _are_ printed if the definition of the operand value was not printed yet.
This happens:
* if the block with the definition appears after the block where the operand's instruction is located
* if a block or instruction is printed in isolation, e.g. in a debugger
The old behavior can be restored with `-Xllvm -sil-print-types`.
This option is added to many existing test files which check for operand types in their check-lines.
getVarInfo() now always returns a variable with a location and scope.
To opt out of this change, getVarInfo(false) returns an incomplete variable.
This can be used to work around bugs, but should only really be used for
printing.
The complete var info will also contain the type, except for debug_values,
as its type depends on another instruction, which may be inconsistent if
called mid-pass.
All locations in debug variables are now also stripped of flags, to avoid
issues when comparing or hashing debug variables.
