net: aquantia: return 'err' if set MPI_DEINIT state fails

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils.c:260:7:
 warning: variable 'err' set but not used [-Wunused-but-set-variable]

'err' should be returned while set MPI_DEINIT state fails
in hw_atl_utils_soft_reset.

Fixes: cce96d18 ("net: aquantia: Regression on reset with 1.x firmware")
Signed-off-by: NYueHaibing <yuehaibing@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/ethernet/aquantia/atlantic/hw_atl/hw_atl_utils.c

@@ -263,6 +263,8 @@ int hw_atl_utils_soft_reset(struct aq_hw_s *self)
 		AQ_HW_WAIT_FOR((aq_hw_read_reg(self, HW_ATL_MPI_STATE_ADR) &
 				HW_ATL_MPI_STATE_MSK) == MPI_DEINIT,
 			       10, 1000U);
+		if (err)
+			return err;
 	}
 
 	if (self->rbl_enabled)