Integrate new result macros. (#1780)

* result: try out some experimental shenanigans

* result: sketch out some more shenanigans

* result: see what it looks like to convert kernel to use result conds instead of guards

* make rest of kernel use experimental new macro-ing

libraries/libmesosphere/source/kern_k_memory_block_manager.cpp

@@ -102,7 +102,7 @@ namespace ams::kern {
         start_block->Initialize(m_start_address, (m_end_address - m_start_address) / PageSize, KMemoryState_Free, KMemoryPermission_None, KMemoryAttribute_None);
         m_memory_block_tree.insert(*start_block);
 
-        return ResultSuccess();
+        R_SUCCEED();
     }
 
     void KMemoryBlockManager::Finalize(KMemoryBlockSlabManager *slab_manager) {