[openwrt/openwrt] bcm53xx: drop dead upgrade code

[LEDE Commits]

rmilecki pushed a commit to openwrt/openwrt.git, branch master:
https://git.openwrt.org/a6dc0f680d3715322abd7a5dc1426f56274292ac

commit a6dc0f680d3715322abd7a5dc1426f56274292ac
Author: Rafał Miłecki <rafal at milecki.pl>
AuthorDate: Tue Mar 29 16:14:54 2022 +0200

    bcm53xx: drop dead upgrade code
    
    platform_nand_pre_upgrade() is gone since commit 790692dde2b9
    ("base-files: drop support for the platform_nand_pre_upgrade()").
    
    Signed-off-by: Rafał Miłecki <rafal at milecki.pl>
---
 target/linux/bcm53xx/base-files/lib/upgrade/platform.sh | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/target/linux/bcm53xx/base-files/lib/upgrade/platform.sh b/target/linux/bcm53xx/base-files/lib/upgrade/platform.sh
index c92dcd1e4e..62a36dac49 100644
--- a/target/linux/bcm53xx/base-files/lib/upgrade/platform.sh
+++ b/target/linux/bcm53xx/base-files/lib/upgrade/platform.sh
@@ -403,11 +403,3 @@ platform_do_upgrade() {
 		;;
 	esac
 }
-
-platform_nand_pre_upgrade() {
-	case "$(board_name)" in
-	meraki,mr32)
-		CI_KERNPART="part.safe"
-		;;
-	esac
-}