fix: extend LOTUS_CHAIN_BADGERSTORE_DISABLE_FSYNC to the markset

Without doing this walking a badger markset on a non-nvme knocks the
node hopelessly out of sync during a compaction.

node/repo/fsrepo.go

@@ -27,6 +27,7 @@ import (
 	"github.com/filecoin-project/lotus/node/config"
 	"github.com/filecoin-project/lotus/storage/sealer/fsutil"
 	"github.com/filecoin-project/lotus/storage/sealer/storiface"
+	"github.com/filecoin-project/lotus/system"
 )
 
 const (
@@ -479,19 +480,8 @@ func (fsr *fsLockedRepo) Blockstore(ctx context.Context, domain BlockstoreDomain
 			return
 		}
 
-		//
-		// Tri-state environment variable LOTUS_CHAIN_BADGERSTORE_DISABLE_FSYNC
-		// - unset == the default (currently fsync enabled)
-		// - set with a false-y value == fsync enabled no matter what a future default is
-		// - set with any other value == fsync is disabled ignored defaults (recommended for day-to-day use)
-		//
-		if nosyncBs, nosyncBsSet := os.LookupEnv("LOTUS_CHAIN_BADGERSTORE_DISABLE_FSYNC"); nosyncBsSet {
-			nosyncBs = strings.ToLower(nosyncBs)
-			if nosyncBs == "" || nosyncBs == "0" || nosyncBs == "false" || nosyncBs == "no" {
-				opts.SyncWrites = true
-			} else {
-				opts.SyncWrites = false
-			}
+		if system.BadgerFsyncDisable {
+			opts.SyncWrites = false
 		}
 
 		bs, err := badgerbs.Open(opts)