net: lan78xx: Fix misplaced tasklet_schedule() call

Commit 136f55f6 ("net: lan78xx: fix rx handling before first
packet is send") was not correctly backported to 4.4.  The call to
tasklet_schedule() belongs in lan78xx_link_reset().

Fixes: d1fc12d8 ("net: lan78xx: fix rx handling before first packet is send")
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>