Fix user apps randomly crashing (APIC, GDT layout, syscall entry)

libmsl/m/proc.h

@@ -17,7 +17,7 @@
 #include <stdint.h>
 
 int m_proc_quit (void);
-int m_proc_test (void);
+int m_proc_test (char c);
 int m_proc_map (uintptr_t paddr, uintptr_t vaddr, size_t pages, uint32_t flags);
 int m_proc_unmap (uintptr_t vaddr, size_t pages);
 int m_proc_create_resource_mem (size_t pages, int vis, uintptr_t* out_paddr);