Removing uses of Sleep/SwitchToThread/etc.

src/xenia/kernel/apps/xmp_app.cc

@@ -32,7 +32,7 @@ XXMPApp::XXMPApp(KernelState* kernel_state)
 X_RESULT XXMPApp::XMPGetStatus(uint32_t state_ptr) {
   // Some stupid games will hammer this on a thread - induce a delay
   // here to keep from starving real threads.
-  Sleep(1);
+  xe::threading::Sleep(std::chrono::milliseconds::duration(1));
 
   XELOGD("XMPGetStatus(%.8X)", state_ptr);
   xe::store_and_swap<uint32_t>(memory_->TranslateVirtual(state_ptr),

src/xenia/kernel/xboxkrnl_audio_xma.cc

@@ -345,7 +345,7 @@ SHIM_CALL XMABlockWhileInUse_shim(PPCContext* ppc_context,
     if (!context.input_buffer_0_valid && !context.input_buffer_1_valid) {
       break;
     }
-    Sleep(1);
+    xe::threading::Sleep(std::chrono::milliseconds::duration(1));
   } while (true);
 
   SHIM_SET_RETURN_32(0);

src/xenia/kernel/xboxkrnl_rtl.cc

@@ -14,6 +14,7 @@
 #include "xenia/base/atomic.h"
 #include "xenia/base/logging.h"
 #include "xenia/base/string.h"
+#include "xenia/base/threading.h"
 #include "xenia/kernel/kernel_state.h"
 #include "xenia/kernel/xboxkrnl_private.h"
 #include "xenia/kernel/objects/xthread.h"
@@ -398,7 +399,7 @@ spin:
     // TODO(benvanik): contention - do a real wait!
     // XELOGE("RtlEnterCriticalSection tried to really lock!");
     spin_wait_remaining = 0;  // HACK: spin forever
-    SwitchToThread();
+    xe::threading::MaybeYield();
     goto spin;
   }