Rollup merge of #128539 - biabbas:deny_unsafe, r=workingjubilee

Forbid unused unsafe in vxworks-specific std modules

Tracking issue #127747
Adding deny(unsafe_op_in_unsafe_fn) in VxWorks specific files did not cause any error.
Most of VxWorks falls back on Unix libraries. So we'll have to wait for Unix changes.

r? ```@workingjubilee```

Author: matthiaskrgr