[openwrt/openwrt] d1: enable overlay support

[LEDE Commits]

wigyori pushed a commit to openwrt/openwrt.git, branch main:
https://git.openwrt.org/1e7950a45de593354a508d80a39951b440336ab7

commit 1e7950a45de593354a508d80a39951b440336ab7
Author: Chukun Pan <amadeus at jmu.edu.cn>
AuthorDate: Mon Oct 20 22:16:21 2025 +0800

    d1: enable overlay support
    
    Add the loop module and mkfs tool to use f2fs/ext4
    based overlays. This fixes the following bug:
    
    mount_root: unable to create loop device
    mount_root: no usable overlay filesystem found, using tmpfs overlay
    
    Fixes: 99545b4bb1faf7c3 ("d1: add new target")
    Signed-off-by: Chukun Pan <amadeus at jmu.edu.cn>
---
 target/linux/d1/Makefile    | 2 ++
 target/linux/d1/config-6.12 | 1 +
 2 files changed, 3 insertions(+)

diff --git a/target/linux/d1/Makefile b/target/linux/d1/Makefile
index 0d30c8233c..cd3b1495eb 100644
--- a/target/linux/d1/Makefile
+++ b/target/linux/d1/Makefile
@@ -15,6 +15,8 @@ KERNEL_PATCHVER:=6.12
 
 include $(INCLUDE_DIR)/target.mk
 
+DEFAULT_PACKAGES += e2fsprogs f2fsck mkf2fs
+
 define Target/Description
 	Build firmware images for Allwinner D1 RISC-V boards
 endef
diff --git a/target/linux/d1/config-6.12 b/target/linux/d1/config-6.12
index fc733f3455..53d5319030 100644
--- a/target/linux/d1/config-6.12
+++ b/target/linux/d1/config-6.12
@@ -23,6 +23,7 @@ CONFIG_ARCH_WANTS_THP_SWAP=y
 CONFIG_ASN1=y
 CONFIG_ASSOCIATIVE_ARRAY=y
 # CONFIG_AX45MP_L2_CACHE is not set
+CONFIG_BLK_DEV_LOOP=y
 CONFIG_BLK_DEV_SD=y
 CONFIG_BLK_MQ_PCI=y
 CONFIG_CC_HAVE_STACKPROTECTOR_TLS=y