kernel: Fix build errors.

src/core/hle/kernel/k_thread.cpp

@@ -1015,8 +1015,13 @@ ResultVal<std::shared_ptr<KThread>> KThread::Create(Core::System& system, Thread
 
     std::shared_ptr<KThread> thread = std::make_shared<KThread>(kernel);
 
-    thread->InitializeThread(thread.get(), entry_point, arg, stack_top, priority, processor_id,
-                             owner_process, type_flags);
+    if (const auto result =
+            thread->InitializeThread(thread.get(), entry_point, arg, stack_top, priority,
+                                     processor_id, owner_process, type_flags);
+        result.IsError()) {
+        return result;
+    }
+
     thread->name = name;
 
     auto& scheduler = kernel.GlobalSchedulerContext();

src/core/hle/kernel/kernel.cpp

@@ -117,14 +117,14 @@ struct KernelCore::Impl {
     void InitializePhysicalCores() {
         exclusive_monitor =
             Core::MakeExclusiveMonitor(system.Memory(), Core::Hardware::NUM_CPU_CORES);
-        for (s32 i = 0; i < Core::Hardware::NUM_CPU_CORES; i++) {
+        for (u32 i = 0; i < Core::Hardware::NUM_CPU_CORES; i++) {
             schedulers[i] = std::make_unique<Kernel::KScheduler>(system, i);
             cores.emplace_back(i, system, *schedulers[i], interrupts);
         }
     }
 
     void InitializeSchedulers() {
-        for (s32 i = 0; i < Core::Hardware::NUM_CPU_CORES; i++) {
+        for (u32 i = 0; i < Core::Hardware::NUM_CPU_CORES; i++) {
             cores[i].Scheduler().Initialize();
         }
     }