x86: Add reserve_ebda_region to x86_init_ops

reserve_ebda_region needs to be called befor start_kernel. Moorestown
needs to override it. Make it a x86_init_ops function and initialize
it with the default reserve_ebda_region.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/include/asm/x86_init.h

@@ -6,11 +6,13 @@
  * @probe_roms:			probe BIOS roms
  * @reserve_resources:		reserve the standard resources for the
  *				platform
+ * @reserve_ebda_region:	reserve the extended bios data area
  *
  */
 struct x86_init_resources {
 	void (*probe_roms)(void);
 	void (*reserve_resources)(void);
+	void (*reserve_ebda_region)(void);
 };
 
 /**