exiv2: use the new gettext logic

This commit switches to use the new gettext logic, which involves:

 - using TARGET_NLS_DEPENDENCIES instead of hand-encoded dependencies
   on gettext/host-gettext

 - using BR2_SYSTEM_ENABLE_NLS instead of BR2_ENABLE_LOCALE to decide
   if NLS support should be enabled or not

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

package/exiv2/exiv2.mk

@@ -42,11 +42,10 @@ else
 EXIV2_CONF_OPTS += -DEXIV2_ENABLE_XMP=OFF -DEXIV2_ENABLE_LIBXMP=OFF
 endif
 
-ifeq ($(BR2_ENABLE_LOCALE),y)
+EXIV2_DEPENDENCIES += $(TARGET_NLS_DEPENDENCIES)
+
+ifeq ($(BR2_SYSTEM_ENABLE_NLS),y)
 EXIV2_CONF_OPTS += -DEXIV2_ENABLE_NLS=ON
-ifeq ($(BR2_PACKAGE_GETTEXT),y)
-EXIV2_DEPENDENCIES += gettext
-endif
 else
 EXIV2_CONF_OPTS += -DEXIV2_ENABLE_NLS=OFF
 endif