ipq40xx: 5.4: enable NAND

Lets enable RAW NAND and Qcom NANDC drivers again in kernel 5.4.
They were dropped when 5.4 support was introduced due to upstream
changing the symbol names so refreshing was not enough.

Signed-off-by: Robert Marko <[email protected]>
[cut long line in commit message, enabled BCH as well]
Signed-off-by: Christian Lamparter <[email protected]>

target/linux/ipq40xx/config-5.4

@@ -70,6 +70,7 @@ CONFIG_ARM_UNWIND=y
 CONFIG_ARM_VIRT_EXT=y
 CONFIG_AT803X_PHY=y
 CONFIG_AUTO_ZRELADDR=y
+CONFIG_BCH=y
 CONFIG_BINFMT_FLAT_ARGVP_ENVP_ON_STACK=y
 CONFIG_BLK_DEV_LOOP=y
 CONFIG_BLK_MQ_PCI=y
@@ -336,6 +337,10 @@ CONFIG_MODULES_USE_ELF_REL=y
 # CONFIG_MSM_MMCC_8996 is not set
 CONFIG_MTD_CMDLINE_PARTS=y
 CONFIG_MTD_NAND_CORE=y
+CONFIG_MTD_NAND_ECC_SW_BCH=y
+CONFIG_MTD_NAND_ECC_SW_HAMMING=y
+CONFIG_MTD_NAND_QCOM=y
+CONFIG_MTD_RAW_NAND=y
 CONFIG_MTD_SPI_NAND=y
 CONFIG_MTD_SPI_NOR=y
 CONFIG_MTD_SPLIT_FIRMWARE=y