translate-c: Ensure assignments are within a block when necessary

Ensures that if an assignment statement is the sole statement within a
C if statement, for loop, do loop, or do while loop, then when translated
it resides within a block, even though it does not in the original C.

Fixes the following invalid translation:

`if (1) if (1) 2;` -> `if (true) if (true) _ = @as(c_int, 2);`

To this:
```zig
    if (true) if (true) {
        _ = @as(c_int, 2);
    };
```

Fixes #8159

0 files changed, 0 insertions, 0 deletions