x86: extend e820 early_res support 32bit -fix #3

introduce init_pg_table_start, so xen PV could specify the value.

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/asm-x86/setup.h b/include/asm-x86/setup.h
index ffa0f54..64f5f0c1 100644
--- a/include/asm-x86/setup.h
+++ b/include/asm-x86/setup.h
@@ -59,10 +59,12 @@
 void __init add_memory_region(unsigned long long start,
 			      unsigned long long size, int type);
 
+
+void __init i386_start_kernel(void);
+
+extern unsigned long init_pg_tables_start;
 extern unsigned long init_pg_tables_end;
 
-
-
 #endif /* __i386__ */
 #endif /* _SETUP */
 #endif /* __ASSEMBLY__ */