zlib: remove dedicated target-headers option

Instead, simply only copy headers/static lib if BR2_HAVE_DEVFILES
is enabled.

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

package/zlib/Config.in

@@ -5,9 +5,3 @@ config BR2_PACKAGE_ZLIB
 	  gzip and libpng.
 
 	  http://www.gzip.org/zlib/
-
-config BR2_PACKAGE_ZLIB_TARGET_HEADERS
-	bool "zlib headers in target"
-	depends on BR2_PACKAGE_ZLIB
-	help
-	  Put headers files in the target.

package/zlib/zlib.mk

@@ -68,9 +68,7 @@ $(TARGET_DIR)/usr/lib/libz.a: $(STAGING_DIR)/usr/lib/libz.a
 	$(INSTALL) -D $(STAGING_DIR)/usr/lib/libz.a $(TARGET_DIR)/usr/lib/libz.a
 	touch -c $@
 
-zlib-headers: $(TARGET_DIR)/usr/lib/libz.a
-
-zlib: $(ZLIB_TARGET)
+zlib: $(ZLIB_TARGET) $(if $(BR2_HAVE_DEVFILES,$(TARGET_DIR)/usr/lib/libz.a)
 
 zlib-source: $(DL_DIR)/$(ZLIB_SOURCE)
 
@@ -94,6 +92,3 @@ zlib-dirclean:
 ifeq ($(BR2_PACKAGE_ZLIB),y)
 TARGETS+=zlib
 endif
-ifeq ($(BR2_PACKAGE_ZLIB_TARGET_HEADERS),y)
-TARGETS+=zlib-headers
-endif