kernel: add recently introduced CONFIG_MTD_SPLIT_ELF_FW

The config symbol was introduced in drivers, but not added to
generic kernel config files. This will halt build asking for the
value.

Fix it by adding the value (setting it to disabled).

Fixes: 3f7047db7aaf ("kernel: mtdsplit: support ELF loader splitting")

Signed-off-by: Adrian Schmutzler <[email protected]>

target/linux/generic/config-4.19

@@ -3033,6 +3033,7 @@ CONFIG_MTD_SPI_NOR_USE_4K_SECTORS_LIMIT=4096
 CONFIG_MTD_SPLIT=y
 # CONFIG_MTD_SPLIT_BCM_WFI_FW is not set
 # CONFIG_MTD_SPLIT_BRNIMAGE_FW is not set
+# CONFIG_MTD_SPLIT_ELF_FW is not set
 # CONFIG_MTD_SPLIT_EVA_FW is not set
 # CONFIG_MTD_SPLIT_FIRMWARE is not set
 CONFIG_MTD_SPLIT_FIRMWARE_NAME="firmware"

target/linux/generic/config-5.4

@@ -3259,6 +3259,7 @@ CONFIG_MTD_SPI_NOR_USE_4K_SECTORS_LIMIT=4096
 CONFIG_MTD_SPLIT=y
 # CONFIG_MTD_SPLIT_BCM_WFI_FW is not set
 # CONFIG_MTD_SPLIT_BRNIMAGE_FW is not set
+# CONFIG_MTD_SPLIT_ELF_FW is not set
 # CONFIG_MTD_SPLIT_EVA_FW is not set
 # CONFIG_MTD_SPLIT_FIRMWARE is not set
 CONFIG_MTD_SPLIT_FIRMWARE_NAME="firmware"