Fix Clippy 1.89 warnings (#1367)

Clippy 1.89 starts to warn about `mismatched_lifetime_syntaxes`. We fix
our function signatures by adding `'_` in the return types.

Author: wks

src/plan/global.rs

@@ -410,7 +410,7 @@ impl<VM: VMBinding> CreateSpecificPlanArgs<'_, VM> {
         zeroed: bool,
         permission_exec: bool,
         vmrequest: VMRequest,
-    ) -> PlanCreateSpaceArgs<VM> {
+    ) -> PlanCreateSpaceArgs<'_, VM> {
         PlanCreateSpaceArgs {
             name,
             zeroed,

src/scheduler/worker.rs

@@ -111,11 +111,11 @@ const STAT_BORROWED_MSG: &str = "GCWorkerShared.stat is already borrowed.  This
     the mutator calls harness_begin or harness_end while the GC is running.";
 
 impl<VM: VMBinding> GCWorkerShared<VM> {
-    pub fn borrow_stat(&self) -> AtomicRef<WorkerLocalStat<VM>> {
+    pub fn borrow_stat(&self) -> AtomicRef<'_, WorkerLocalStat<VM>> {
         self.stat.try_borrow().expect(STAT_BORROWED_MSG)
     }
 
-    pub fn borrow_stat_mut(&self) -> AtomicRefMut<WorkerLocalStat<VM>> {
+    pub fn borrow_stat_mut(&self) -> AtomicRefMut<'_, WorkerLocalStat<VM>> {
         self.stat.try_borrow_mut().expect(STAT_BORROWED_MSG)
     }
 }

src/util/heap/externalpageresource.rs

@@ -77,7 +77,7 @@ impl<VM: VMBinding> ExternalPageResource<VM> {
         lock.push(pages);
     }
 
-    pub fn get_external_pages(&self) -> MutexGuard<Vec<ExternalPages>> {
+    pub fn get_external_pages(&self) -> MutexGuard<'_, Vec<ExternalPages>> {
         self.ranges.lock().unwrap()
     }
 }

src/util/heap/layout/map32.rs

@@ -268,7 +268,7 @@ impl Map32 {
     /// Get a mutable reference to the inner Map32Inner with a lock.
     /// The caller should only use the mutable reference while holding the lock.
     #[allow(clippy::mut_from_ref)]
-    fn mut_self_with_sync(&self) -> (MutexGuard<()>, &mut Map32Inner) {
+    fn mut_self_with_sync(&self) -> (MutexGuard<'_, ()>, &mut Map32Inner) {
         let guard = self.sync.lock().unwrap();
         (guard, unsafe { self.mut_self() })
     }

src/vm/tests/mock_tests/mock_test_doc_weakref_code_example.rs

@@ -16,7 +16,8 @@ struct VMScanning;
 // Just to make the code example look better.
 use MockVM as MyVM;
 
-// Placeholders for functions supposed to be implemented byu the VM.
+// Placeholders for functions supposed to be implemented by the VM.
+#[allow(dead_code)]
 mod my_vm {
     use crate::util::ObjectReference;