unneeded unsafe

Author: nia-e

src/alloc/isolated_alloc.rs

@@ -233,9 +233,7 @@ impl IsolatedAlloc {
             // FIXME: this can lead to threshold effects, we should probably add some form
             // of hysteresis.
             if pinfo.is_empty() {
-                // SAFETY: `self.page_size` is always a power of 2 and does not overflow an isize
-                let page_layout =
-                    unsafe { Layout::from_size_align_unchecked(self.page_size, self.page_size) };
+                let page_layout = Layout::from_size_align(self.page_size, self.page_size).unwrap();
                 self.page_infos.remove(idx_of_pinfo);
                 // SAFETY: We checked that there are no outstanding allocations
                 // from us pointing to this page, and we know it was allocated