add generic system call forwarding

kernel/include/process.h

@@ -40,6 +40,7 @@ struct vm_regions {
 	unsigned long brk_start, brk_end;
 	unsigned long map_start, map_end;
 	unsigned long stack_start, stack_end;
+	unsigned long user_start, user_end;
 };
 
 struct process_vm;

kernel/include/syscall.h

@@ -89,7 +89,10 @@ struct program_load_desc {
 	int cpu;
 	int pid;
 	unsigned long entry;
+	unsigned long user_start;
+	unsigned long user_end;
 	unsigned long rprocess;
+	unsigned long rpgtable;
 	unsigned long at_phdr;
 	unsigned long at_phent;
 	unsigned long at_phnum;