devices: replace as <pointer> casts with safer alternatives

`as` casts can change mutability, which quickly leads to undefined
behavior.

Signed-off-by: Julian Schindel <mail@arctic-alpaca.de>

devices/src/legacy/cmos.rs

@@ -122,13 +122,13 @@ impl BusDevice for Cmos {
                 // the tm and timespec struct because it contains only plain data.
                 let update_in_progress = unsafe {
                     let mut timespec: timespec = mem::zeroed();
-                    clock_gettime(CLOCK_REALTIME, &mut timespec as *mut _);
+                    clock_gettime(CLOCK_REALTIME, &raw mut timespec);
 
                     // https://github.com/rust-lang/libc/issues/1848
                     #[cfg_attr(target_env = "musl", allow(deprecated))]
                     let now: time_t = timespec.tv_sec;
                     let mut tm: tm = mem::zeroed();
-                    gmtime_r(&now, &mut tm as *mut _);
+                    gmtime_r(&now, &raw mut tm);
 
                     // The following lines of code are safe but depend on tm being in scope.
                     seconds = tm.tm_sec;

devices/src/pvmemcontrol.rs

@@ -443,7 +443,7 @@ impl PvmemcontrolBusDevice {
             )));
         };
         assert!(slice.len() >= range_len);
-        let res = f(slice.ptr_guard_mut().as_ptr() as _, slice.len());
+        let res = f(slice.ptr_guard_mut().as_ptr().cast(), slice.len());
         if res != 0 {
             return Err(Error::LibcFail(io::Error::last_os_error()));
         }