octeontx2-pf: Fix linking objects into multiple modules

[ Upstream commit 1062d038 ]

This patch fixes the below build warning messages that are
caused due to linking same files to multiple modules by
exporting the required symbols.

"scripts/Makefile.build:244: drivers/net/ethernet/marvell/octeontx2/nic/Makefile:
otx2_devlink.o is added to multiple modules: rvu_nicpf rvu_nicvf

scripts/Makefile.build:244: drivers/net/ethernet/marvell/octeontx2/nic/Makefile:
otx2_dcbnl.o is added to multiple modules: rvu_nicpf rvu_nicvf"

Fixes: 8e675581

 ("octeontx2-pf: PFC config support with DCBx").
Signed-off-by: Geetha sowjanya <gakula@marvell.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>