ar71xx: fix HiveAP 121 PLL for 1000M

The Aerohive HiveAP 121 has the wrong PLL value set for Gigabit speeds,
leading to packet-loss. 10M and 100M work fine.

This commit sets the Gigabit Ethernet PLL value to the correct value,
fixing packet loss.

Confirmed with iperf and floodping.

Signed-off-by: David Bauer <mail@david-bauer.net>
(cherry picked from commit cb49e46a8a4526d86270ced3ba3aa90225ca82d7)

target/linux/ar71xx/files/arch/mips/ath79/mach-hiveap-121.c

@@ -111,7 +111,7 @@ static void __init hiveap_121_setup(void)
 	ath79_eth0_data.mii_bus_dev = &ath79_mdio0_device.dev;
 	ath79_eth0_data.phy_if_mode = PHY_INTERFACE_MODE_RGMII;
 	ath79_eth0_data.phy_mask = BIT(HIVEAP_121_LAN_PHYADDR);
-	ath79_eth0_pll_data.pll_1000 = 0x0e000000;
+	ath79_eth0_pll_data.pll_1000 = 0x06000000;
 	ath79_eth0_pll_data.pll_100 = 0x00000101;
 	ath79_eth0_pll_data.pll_10 = 0x00001313;
 	ath79_register_eth(0);