Replace all instances of wwlog.Printf

wwlog provides named loggers for each level, which requires
less code and is clearer than wwlog.Printf. The code has
included a mix of both, but this commit consolidates existing
code on the per-level functions.

Signed-off-by: Jonathon Anderson <janderson@ciq.co>

internal/pkg/configure/nfs.go

@@ -19,7 +19,7 @@ func NFS() error {
 
 	controller, err := warewulfconf.New()
 	if err != nil {
-		wwlog.Printf(wwlog.ERROR, "%s\n", err)
+		wwlog.Error("%s\n", err)
 		os.Exit(1)
 	}
 
@@ -30,10 +30,10 @@ func NFS() error {
 		if controller.Warewulf.EnableHostOverlay {
 			err = overlay.BuildHostOverlay()
 			if err != nil {
-				wwlog.Printf(wwlog.WARN, "host overlay could not be built: %s\n", err)
+				wwlog.Warn("host overlay could not be built: %s\n", err)
 			}
 		} else {
-			wwlog.Printf(wwlog.INFO, "host overlays are disabled, did not modify exports")
+			wwlog.Info("host overlays are disabled, did not modify exports")
 		}
 		fmt.Printf("Enabling and restarting the NFS services\n")
 		if controller.Nfs.SystemdName == "" {