Merge branch 'hns-phy-loopback'

Lin Yun Sheng says:

====================
Add loopback support in phy_driver and hns ethtool fix

This Patch Set add set_loopback in phy_driver and use it to setup loopback
when doing ethtool phy self_test.

Patch V8:
	Respin the Patch based on net-next

Patch V7:
	1. Add comment why resume the phy in hns_nic_config_phy_loopback.
	2. Fix a typo error in patch description.

Patch V6:
	Fix Or'ing error code in __lb_setup.

Patch V5:
	Removing non loopback related code change.

Patch V4:
	1. Remove c45 checking
	2. Add -ENOTSUPP when function pointer is null,
	   take mutex in phy_loopback.

Patch V3:
	Calling phy_loopback enable and disable in pair in hns mac driver.

Patch V2:
	1. Add phy_loopback in phy_device.c.
	2. Do error checking and do the read and write once in
	   genphy_loopback.
	3. Remove gen10g_loopback in phy_device.c.

Patch V1:
	Initial Submit
====================

Signed-off-by: David S. Miller <davem@davemloft.net>