Kernel/Memory: Give each Process its own page table.

The loader is in charge of setting the newly created process's page table as the main one during the loading process.

src/core/loader/elf.cpp

@@ -397,6 +397,7 @@ ResultStatus AppLoader_ELF::Load() {
     Kernel::g_current_process = Kernel::Process::Create(std::move(codeset));
     Kernel::g_current_process->svc_access_mask.set();
     Kernel::g_current_process->address_mappings = default_address_mappings;
+    Memory::current_page_table = &Kernel::g_current_process->vm_manager.page_table;
 
     // Attach the default resource limit (APPLICATION) to the process
     Kernel::g_current_process->resource_limit =