net: phylink: remove switch() statement in resolve handling

The switch() statement doesn't sit very well with the preceeding if()
statements, so let's just convert everything to if()s. As a result of
the two preceding commits, there is now only one case in the switch()
statement. Remove the switch statement and reduce the code indentation.
Code reformatting will be in the following commit.

Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Link: https://patch.msgid.link/E1t9RQu-002Fez-AA@rmk-PC.armlinux.org.uk


Signed-off-by: Jakub Kicinski <kuba@kernel.org>