mediatek: mt7623: disable ecc engine support

There's no board using nand on this target atm.

Signed-off-by: Chuanhong Guo <gch981213@gmail.com>

target/linux/mediatek/mt7623/config-5.15

@@ -380,6 +380,7 @@ CONFIG_MODULES_USE_ELF_REL=y
 # CONFIG_MOUSE_SERIAL is not set
 # CONFIG_MOUSE_VSXXXAA is not set
 CONFIG_MTD_CMDLINE_PARTS=y
+# CONFIG_MTD_NAND_ECC_MEDIATEK is not set
 CONFIG_MTD_SPI_NOR=y
 CONFIG_MTD_SPLIT_FIRMWARE=y
 CONFIG_MTD_SPLIT_UIMAGE_FW=y
@@ -400,7 +401,6 @@ CONFIG_MTK_PMIC_WRAP=y
 CONFIG_MTK_SCPSYS=y
 CONFIG_MTK_SCPSYS_PM_DOMAINS=y
 CONFIG_MTK_SMI=y
-# CONFIG_MTK_SPI_NAND is not set
 CONFIG_MTK_THERMAL=y
 CONFIG_MTK_TIMER=y
 # CONFIG_MTK_UART_APDMA is not set