[U-Boot] [PATCH 07/45] Makefile: Add a warning if SPL/TPL cannot be built

[sjg at google.com]

At present the build fails in strange ways if CONFIG_SPL is defined by
CONFIG_SUPPORT_SPL is not. Add a warning for this case as it can be very
confusing to debug.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 scripts/Makefile.spl | 7 +++++++
 1 file changed, 7 insertions(+)

Applied to u-boot-dm