[sdk] make sure .config gets copied as file

When using scripts/env, .config is most likely a symbolic link
pointing to env/.config. Previously the symbolic link got
copied as-is into the SDK tarball, leading to a dangling .config
symlink on the target system which prevented the SDK from working.


git-svn-id: svn://svn.openwrt.org/openwrt/trunk@29927 3c298f89-4303-0410-b956-a3cf2f4a3e73

target/sdk/Makefile

@@ -40,7 +40,7 @@ $(BIN_DIR)/$(SDK_NAME).tar.bz2: clean
 	rm -rf \
 		$(SDK_BUILD_DIR)/target/linux/*/files \
 		$(SDK_BUILD_DIR)/target/linux/*/patches
-	$(CP) \
+	$(CP) -L \
 		$(TOPDIR)/LICENSE \
 		$(TOPDIR)/rules.mk \
 		$(TOPDIR)/.config \