fix blocks.div_ceil(len, bs)

Might as well make the same fix right above: https://github.com/uutils/findutils/blob/5235d782916f51b31ba9e1f41fae717ba6dfd871/src/find/matchers/printf.rs#L396 Side note: I think the code here is wrong, but that can be fixed in a different PR. It should be more like ```rust let blocks = meta()?.blocks(); let len = blocks * STANDARD_BLOCK_SIZE; let bs = if *large_blocks { 1024 } else { 512 }; blocks.div_ceil(len, bs) ``` _Originally posted by @tavianator in https://github.com/uutils/findutils/pull/522#discussion_r2027152154_