doctrine: refers to owning side field which does not exist (again)
<p>Can't wrap my head around it. I more or less copied from the tutorial, but the profiler throws two errors:</p>

<blockquote>
  <p>AppBundle\Entity\Brand The association AppBundle\Entity\Brand#devices
  refers to the owning side field AppBundle\Entity\Device#brands which
  does not exist.</p>
  
  <p>AppBundle\Entity\Device The association AppBundle\Entity\Device#brand
  refers to the inverse side field AppBundle\Entity\Brand#brands which
  does not exist.</p>
</blockquote>

<pre><code>class Brand {

    /**
     * @var int
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

...

    /**
     * @ORM\OneToMany(targetEntity="Device", mappedBy="brands")
     */
    private $devices;
}
</code></pre>

<p>and</p>

<pre><code>class Device {
    /**
     * @var int
     * @ORM\Id
     * @ORM\Column(name="id", type="integer")
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

...

    /**
     * @ORM\ManyToOne(targetEntity="Brand", inversedBy="devices")
     * @ORM\JoinColumn(name="brand_id", referencedColumnName="id", nullable=true)
     */
    private $brand;
}
</code></pre>