cmcc_a10-ubootmod stands for custom U-Boot layout in ImmortalWrt 23.05, add compat version to avoid bricking devices. For 24.10+ users you can just ignore the compat warning. Signed-off-by: Tianling Shen <cnsztl@immortalwrt.org> (cherry picked from commit 4b000293b20b03a45130e6453f3e2a28dc0950ca)