buildroot; move defconfigs to configs/ and print in help

As discussed earlier on the mailing list. It simplifies code, gives more
sensible error message on typos and makes the defconfigs easier to find
for users.

Furthermore, update documentation to match.

Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>

1 files changed, 6 insertions, 3 deletions

diff --git a/Makefile b/Makefile
index 5497c9b45..bbd49d415 100644
--- a/Makefile
+++ b/Makefile
@@ -591,9 +591,9 @@ endif # ifeq ($(BR2_HAVE_DOT_CONFIG),y)
 flush:
 	rm -f $(BUILD_DIR)/tgt-config.cache
 
-%_defconfig: $(CONFIG)/conf
-	cp $(shell find ./target/ -name $@) .config
-	-@$(MAKE) oldconfig
+%_defconfig: $(TOPDIR)/configs/%_defconfig
+	cp $^ .config
+	@$(MAKE) oldconfig
 
 configured: dirs host-sed kernel-headers uclibc-config busybox-config linux26-config
 
@@ -628,6 +628,9 @@ help:
 	@echo '  external-deps          - list external packages used'
 	@echo '  flush                  - flush configuration cache'
 	@echo
+	@$(foreach b, $(notdir $(wildcard $(TOPDIR)/configs/*_defconfig)), \
+	  printf "  %-35s - Build for %s\\n" $(b) $(b:_defconfig=);)
+	@echo
 	@echo 'See docs/README and docs/buildroot.html for further details'
 	@echo