As an effect of revisions 1.261, BUILD_CMD was changed so $(DIRS)

wasn't respected when using it to build different parts of OpenSSL.
1.269 was an attempt to correct that, but unfortunately meant that we
built every part that was given i $(DIRS) 7 times.  This change puts
back the original intent with BUILD_CMD via the new macro
BUILD_ONE_CMD while keeping the intent with RECURSIVE_BUILD_CMD.

Makefile.org

@@ -203,6 +203,10 @@ BUILD_CMD=  if [ -d "$$dir" ]; then \
 	    ) || exit 1; \
 	    fi
 RECURSIVE_BUILD_CMD=for dir in $(DIRS); do $(BUILD_CMD); done
+BUILD_ONE_CMD=\
+	if echo " $(DIRS) " | grep " $$dir " >/dev/null 2>/dev/null; then \
+		$(BUILD_CMD); \
+	fi
 
 reflect:
 	@[ -n "$(THIS)" ] && $(CLEARENV) && $(MAKE) $(THIS) -e $(BUILDENV)
@@ -213,21 +217,21 @@ build_all: build_libs build_apps build_tests build_tools
 build_libs: build_crypto build_ssl build_engines
 
 build_crypto:
-	@dir=crypto; target=all; $(RECURSIVE_BUILD_CMD)
+	@dir=crypto; target=all; $(BUILD_ONE_CMD)
 build_ssl:
-	@dir=ssl; target=all; $(RECURSIVE_BUILD_CMD)
+	@dir=ssl; target=all; $(BUILD_ONE_CMD)
 build_engines:
-	@dir=engines; target=all; $(RECURSIVE_BUILD_CMD)
+	@dir=engines; target=all; $(BUILD_ONE_CMD)
 build_apps:
-	@dir=apps; target=all; $(RECURSIVE_BUILD_CMD)
+	@dir=apps; target=all; $(BUILD_ONE_CMD)
 build_tests:
-	@dir=test; target=all; $(RECURSIVE_BUILD_CMD)
+	@dir=test; target=all; $(BUILD_ONE_CMD)
 build_tools:
-	@dir=tools; target=all; $(RECURSIVE_BUILD_CMD)
+	@dir=tools; target=all; $(BUILD_ONE_CMD)
 
 all_testapps: build_libs build_testapps
 build_testapps:
-	@dir=crypto; target=testapps; $(RECURSIVE_BUILD_CMD)
+	@dir=crypto; target=testapps; $(BUILD_ONE_CMD)
 
 libcrypto$(SHLIB_EXT): libcrypto.a
 	@if [ "$(SHLIB_TARGET)" != "" ]; then \