[openwrt/openwrt] generic: sync mtd rootfs hack with part_bits

[LEDE Commits]

dangole pushed a commit to openwrt/openwrt.git, branch openwrt-22.03:
https://git.openwrt.org/bb596031fa461fdd07e0d3a89759bb2060bfe120

commit bb596031fa461fdd07e0d3a89759bb2060bfe120
Author: Daniel Golle <daniel at makrotopia.org>
AuthorDate: Sat Mar 26 22:51:21 2022 +0000

    generic: sync mtd rootfs hack with part_bits
    
    In commit ab143647ef ("kernel: generic: improve FIT partition parser")
    part_bits was bumped to 2 in order to allow up to 3 additional FIT
    sub-images mapped into sub-partitions.
    This change has to be reflected also in our local patch
    420-mtd-set-rootfs-to-be-root-dev.patch
    which still assumed part_bits==1 for mtdblock devices in case of
    CONFIG_FIT_PARTITION=y.
    
    Fixes: #9557
    Fixes: ab143647ef ("kernel: generic: improve FIT partition parser")
    Signed-off-by: Daniel Golle <daniel at makrotopia.org>
    (cherry picked from commit 13960fb0e0babcd99530fcb234073af0c0a5e2f5)
---
 target/linux/generic/hack-5.10/420-mtd-set-rootfs-to-be-root-dev.patch | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/target/linux/generic/hack-5.10/420-mtd-set-rootfs-to-be-root-dev.patch b/target/linux/generic/hack-5.10/420-mtd-set-rootfs-to-be-root-dev.patch
index 91a91b36ca..b071ac61ec 100644
--- a/target/linux/generic/hack-5.10/420-mtd-set-rootfs-to-be-root-dev.patch
+++ b/target/linux/generic/hack-5.10/420-mtd-set-rootfs-to-be-root-dev.patch
@@ -32,7 +32,7 @@ Signed-off-by: Gabor Juhos <juhosg at openwrt.org>
 +		pr_notice("mtd: device %d (%s) set to be root filesystem\n",
 +			  mtd->index, mtd->name);
 +#ifdef CONFIG_FIT_PARTITION
-+		index <<= 1;
++		index <<= 2;
 +#endif
 +		ROOT_DEV = MKDEV(MTD_BLOCK_MAJOR, index);
 +	}