net: lwip: allow DM_DSA=y when NET_LWIP=y

Now that the DSA tests in test/dm/dsa.c are compatible with NET_LWIP,
remove the dependency of DM_DSA on NET.

Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/net/Makefile b/net/Makefile
index 41edbac..d63f62b 100644
--- a/net/Makefile
+++ b/net/Makefile
@@ -11,7 +11,6 @@
 obj-$(CONFIG_CMD_BOOTP) += bootp.o
 obj-$(CONFIG_CMD_CDP)  += cdp.o
 obj-$(CONFIG_CMD_DNS)  += dns.o
-obj-$(CONFIG_DM_DSA)   += dsa-uclass.o
 obj-$(CONFIG_CMD_LINK_LOCAL) += link_local.o
 obj-$(CONFIG_IPV6)     += ndisc.o
 obj-$(CONFIG_$(PHASE_)DM_ETH) += net.o
@@ -39,6 +38,7 @@
 endif
 
 ifeq ($(filter y,$(CONFIG_NET) $(CONFIG_NET_LWIP)),y)
+obj-$(CONFIG_DM_DSA)   += dsa-uclass.o
 obj-$(CONFIG_$(PHASE_)DM_ETH) += eth-uclass.o
 obj-$(CONFIG_$(PHASE_)BOOTDEV_ETH) += eth_bootdev.o
 obj-$(CONFIG_DM_MDIO)  += mdio-uclass.o