spl: Convert spl_nand_load_image() to use linker list

Add a linker list declaration for this method and remove the explicit
switch() code.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>

common/spl/spl.c

@@ -384,10 +384,6 @@ static int spl_load_image(u32 boot_device)
 		return loader->load_image(&bootdev);
 
 	switch (boot_device) {
-#ifdef CONFIG_SPL_NAND_SUPPORT
-	case BOOT_DEVICE_NAND:
-		return spl_nand_load_image(&bootdev);
-#endif
 #ifdef CONFIG_SPL_ONENAND_SUPPORT
 	case BOOT_DEVICE_ONENAND:
 		return spl_onenand_load_image(&bootdev);

common/spl/spl_nand.c

@@ -67,7 +67,7 @@ static int spl_nand_load_element(int offset, struct image_header *header)
 	}
 }
 
-int spl_nand_load_image(void)
+static int spl_nand_load_image(struct spl_boot_device *bootdev)
 {
 	int err;
 	struct image_header *header;
@@ -145,3 +145,5 @@ int spl_nand_load_image(void)
 	return err;
 }
 #endif
+/* Use priorty 1 so that Ubi can override this */
+SPL_LOAD_IMAGE_METHOD(1, BOOT_DEVICE_NAND, spl_nand_load_image);

include/spl.h

@@ -181,9 +181,6 @@ struct spl_image_loader {
 		.load_image = __method, \
 	}
 
-/* NAND SPL functions */
-int spl_nand_load_image(struct spl_boot_device *bootdev);
-
 /* OneNAND SPL functions */
 int spl_onenand_load_image(struct spl_boot_device *bootdev);