When SPL_NET is included, scripts/Makefile.xpl includes net/. However,
in this directory, the Makefile only compiles things if CONFIG_NET or
CONFIG_NET_LWIP is defined (it doesn't use $(PHASE_)). Therefore, at
least one networking stack needs to be enabled for SPL_NET=y to do
anything meaningful.
In certain cases (e.g. am62px_evm_r5_ethboot_defconfig + NO_NET=y via
menuconfig), it is possible to fail the build with undefined references
(since include/net-common.h does check with CONFIG_IS_ENABLED(NET) which
would be true for SPL_NET, but the implementation wouldn't be compiled).
Fix this oversight by making sure a network stack (and the legacy one)
is available when selecting SPL_NET.
Fixes: 8cb330355b ("net: introduce alternative implementation as net/lwip/")
Reviewed-by: Jerome Forissier <jerome.forissier@linaro.org>
Signed-off-by: Quentin Schulz <quentin.schulz@cherry.de>
cb1d775d25