spl: nand: Introduce spl_nand_get_uboot_raw_page

Introduce weak spl_nand_get_uboot_raw_page, then platform could
have their own implementation.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
Cc: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
Cc: Tien Fong Chee <tien.fong.chee@intel.com>
Cc: Marek Vasut <marex@denx.de>
Cc: Andreas Dannenberg <dannenberg@ti.com>
Cc: Alex Kiernan <alex.kiernan@gmail.com>
Cc: Stefan Roese <sr@denx.de>
Cc: Patrick Delaunay <patrick.delaunay@st.com>
Cc: Miquel Raynal <miquel.raynal@bootlin.com>
Cc: Michal Simek <michal.simek@xilinx.com>
diff --git a/common/spl/spl_nand.c b/common/spl/spl_nand.c
index e2bcefb..d3185dc 100644
--- a/common/spl/spl_nand.c
+++ b/common/spl/spl_nand.c
@@ -11,6 +11,11 @@
 #include <linux/libfdt_env.h>
 #include <fdt.h>
 
+uint32_t __weak spl_nand_get_uboot_raw_page(void)
+{
+	return CONFIG_SYS_NAND_U_BOOT_OFFS;
+}
+
 #if defined(CONFIG_SPL_NAND_RAW_ONLY)
 static int spl_nand_load_image(struct spl_image_info *spl_image,
 			struct spl_boot_device *bootdev)
@@ -21,7 +26,7 @@
 	       CONFIG_SYS_NAND_U_BOOT_OFFS, CONFIG_SYS_NAND_U_BOOT_SIZE,
 	       CONFIG_SYS_NAND_U_BOOT_DST);
 
-	nand_spl_load_image(CONFIG_SYS_NAND_U_BOOT_OFFS,
+	nand_spl_load_image(spl_nand_get_uboot_raw_page(),
 			    CONFIG_SYS_NAND_U_BOOT_SIZE,
 			    (void *)CONFIG_SYS_NAND_U_BOOT_DST);
 	spl_set_header_raw_uboot(spl_image);
@@ -139,7 +144,7 @@
 #endif
 #endif
 	/* Load u-boot */
-	err = spl_nand_load_element(spl_image, CONFIG_SYS_NAND_U_BOOT_OFFS,
+	err = spl_nand_load_element(spl_image, spl_nand_get_uboot_raw_page(),
 				    header);
 #ifdef CONFIG_SYS_NAND_U_BOOT_OFFS_REDUND
 #if CONFIG_SYS_NAND_U_BOOT_OFFS != CONFIG_SYS_NAND_U_BOOT_OFFS_REDUND