net: marvell: prestera: fix patchwork build problems

fix the remaining build issues reported by patchwork
in firmware v4.0 support commit which has been already
merged.

Fix patchwork issues:
 - source inline
 - checkpatch

Fixes: bb5dbf2c ("net: marvell: prestera: add firmware v4.0 support")
Signed-off-by: Volodymyr Mytnyk <vmytnyk@marvell.com>
Signed-off-by: David S. Miller <davem@davemloft.net>