remove dep on udev

- remove the need to map host's /dev
- remove race issues or need to have a working `udevadm settle`

cmd/dkl-local-server/boot-img.go

@@ -148,6 +148,7 @@ func setupBootImage(bootImg *os.File, ctx *renderContext) (err error) {
 	}()
 
 	log.Print("device: ", dev)
+	syncSysToDev()
 
 	tempDir := bootImg.Name() + ".p1.mount"
 
@@ -161,9 +162,10 @@ func setupBootImage(bootImg *os.File, ctx *renderContext) (err error) {
 		os.RemoveAll(tempDir)
 	}()
 
-	err = syscall.Mount(dev+"p1", tempDir, "vfat", 0, "")
+	devp1 := dev + "p1"
+	err = syscall.Mount(devp1, tempDir, "vfat", 0, "")
 	if err != nil {
-		return fmt.Errorf("failed to mount %s to %s: %v", dev+"p1", tempDir, err)
+		return fmt.Errorf("failed to mount %s to %s: %v", devp1, tempDir, err)
 	}
 
 	defer func() {