brcmsmac: fix memory leak in wlc_phy_attach_lcnphy

When wlc_phy_txpwr_srom_read_lcnphy fails in wlc_phy_attach_lcnphy,
the allocated pi->u.pi_lcnphy is leaked, since struct brcms_phy will be
freed in the caller function.

Fix this by calling wlc_phy_detach_lcnphy in the error handler of
wlc_phy_txpwr_srom_read_lcnphy before returning.
Signed-off-by: Keita Suzuki <keitasuzuki.park@sslab.ics.keio.ac.jp>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200908121743.23108-1-keitasuzuki.park@sslab.ics.keio.ac.jp

drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_lcn.c

@@ -5047,8 +5047,10 @@ bool wlc_phy_attach_lcnphy(struct brcms_phy *pi)
 	pi->pi_fptr.radioloftget = wlc_lcnphy_get_radio_loft;
 	pi->pi_fptr.detach = wlc_phy_detach_lcnphy;
 
-	if (!wlc_phy_txpwr_srom_read_lcnphy(pi))
+	if (!wlc_phy_txpwr_srom_read_lcnphy(pi)) {
+		kfree(pi->u.pi_lcnphy);
 		return false;
+	}
 
 	if (LCNREV_IS(pi->pubpi.phy_rev, 1)) {
 		if (pi_lcn->lcnphy_tempsense_option == 3) {