build: update logging statements to make json log work - fixes #6038

This changes log statements from log to fs package, which is required for --use-json-log
to properly make log output in JSON format. The recently added custom linting rule,
handled by ruleguard via gocritic via golangci-lint, warns about these and suggests
the alternative. Fixing was therefore basically running "golangci-lint run --fix",
although some manual fixup of mainly imports are necessary following that.

cmd/siginfo_bsd.go

@@ -3,11 +3,11 @@
 package cmd
 
 import (
-	"log"
 	"os"
 	"os/signal"
 	"syscall"
 
+	"github.com/rclone/rclone/fs"
 	"github.com/rclone/rclone/fs/accounting"
 )
 
@@ -17,7 +17,7 @@ func SigInfoHandler() {
 	signal.Notify(signals, syscall.SIGINFO)
 	go func() {
 		for range signals {
-			log.Printf("%v\n", accounting.GlobalStats())
+			fs.Printf(nil, "%v\n", accounting.GlobalStats())
 		}
 	}()
 }