x86: ivybridge: Drop sandybridge_early_init()

This function was removed in the previous clean-up. Drop it from the header
file also.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

arch/x86/include/asm/arch-ivybridge/sandybridge.h

@@ -113,6 +113,4 @@
  */
 int bridge_silicon_revision(struct udevice *dev);
 
-void sandybridge_early_init(int chipset_type);
-
 #endif