`mt7921u_dma_init` can only return zero or negative number according to its
definition. When it returns non-zero number, there exists an error and this
function should handle this error rather than return directly.
Fixes: 0d2afe09fad5 ("mt76: mt7921: add mt7921u driver")
Signed-off-by: Jiefeng Li <jiefeng_li@hust.edu.cn>
Reviewed-by: Dongliang Mu <dzm91@hust.edu.cn>
Reviewed-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
 
        ret = mt7921u_dma_init(dev, false);
        if (ret)
-               return ret;
+               goto error;
 
        hw = mt76_hw(dev);
        /* check hw sg support in order to enable AMSDU */