at86rf230: add reset states of tx power level

This patch adds the reset states for tx power levels after running reset
procedure.
Signed-off-by: NAlexander Aring <alex.aring@gmail.com>
Signed-off-by: NMarcel Holtmann <marcel@holtmann.org>

drivers/net/ieee802154/at86rf230.c

@@ -1701,6 +1701,7 @@ at86rf230_detect_device(struct at86rf230_local *lp)
 	}
 
 	lp->hw->phy->cca_ed_level = lp->hw->phy->supported.cca_ed_levels[7];
+	lp->hw->phy->transmit_power = lp->hw->phy->supported.tx_powers[0];
 
 not_supp:
 	dev_info(&lp->spi->dev, "Detected %s chip version %d\n", chip, version);