brcm47xx: b44: fix logic in BUG_ON()

It is a problem when phydev is not set at this position and not the other way around.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>


git-svn-id: svn://svn.openwrt.org/openwrt/trunk@38744 3c298f89-4303-0410-b956-a3cf2f4a3e73