include: also check CONFIG_GPIOLIB for GPIO_SUPPORT

Recent kernels removed GENERIC_GPIO and require GPIO capable
targets to select GPIOLIB instead, so check for both symbols.

Fixed #13814.

Signed-off-by: Jonas Gorski <jogo@openwrt.org>

SVN-Revision: 37166

include/target.mk

@@ -163,7 +163,7 @@ ifeq ($(DUMP),1)
     .SILENT: $(TMP_CONFIG)
     .PRECIOUS: $(TMP_CONFIG)
 
-    ifneq ($(CONFIG_GENERIC_GPIO),)
+    ifneq ($(CONFIG_GENERIC_GPIO)$(CONFIG_GPIOLIB),)
       FEATURES += gpio
     endif
     ifneq ($(CONFIG_PCI),)