make use of uapi directory wrapper

SVN-Revision: 34684

package/network/services/ppp/Makefile

@@ -158,7 +158,7 @@ $(call Build/Configure/Default,, \
 	mkdir -p $(PKG_BUILD_DIR)/pppd/plugins/pppoatm/linux
 	cp \
 		$(LINUX_DIR)/include/linux/compiler.h \
-		$(LINUX_DIR)/include/linux/atm*.h \
+		$(LINUX_UAPI_DIR)/linux/atm*.h \
 		$(PKG_BUILD_DIR)/pppd/plugins/pppoatm/linux/
 endef