hw: move NICs to hw/net/, configure via default-configs/

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/default-configs/arm-softmmu.mak b/default-configs/arm-softmmu.mak
index 4b72019..cd353bd 100644
--- a/default-configs/arm-softmmu.mak
+++ b/default-configs/arm-softmmu.mak
@@ -17,6 +17,7 @@
 CONFIG_LM832X=y
 CONFIG_TMP105=y
 CONFIG_STELLARIS_INPUT=y
+CONFIG_STELLARIS_ENET=y
 CONFIG_SSD0303=y
 CONFIG_SSD0323=y
 CONFIG_ADS7846=y