libidn: 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

 - dropping BR2_PACKAGE_GETTEXT selection

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

package/libidn/Config.in

@@ -1,6 +1,5 @@
 config BR2_PACKAGE_LIBIDN
 	bool "libidn"
-	select BR2_PACKAGE_GETTEXT if BR2_NEEDS_GETTEXT_IF_LOCALE
 	help
 	  Libidn's purpose is to encode and decode internationalized
 	  domain names.

package/libidn/libidn.mk

@@ -9,7 +9,7 @@ LIBIDN_SITE = $(BR2_GNU_MIRROR)/libidn
 LIBIDN_INSTALL_STAGING = YES
 LIBIDN_CONF_ENV = EMACS="no"
 LIBIDN_CONF_OPTS = --disable-java --enable-csharp=no
-LIBIDN_DEPENDENCIES = host-pkgconf $(if $(BR2_NEEDS_GETTEXT_IF_LOCALE),gettext) $(if $(BR2_PACKAGE_LIBICONV),libiconv)
+LIBIDN_DEPENDENCIES = host-pkgconf $(TARGET_NLS_DEPENDENCIES) $(if $(BR2_PACKAGE_LIBICONV),libiconv)
 LIBIDN_LICENSE = GPL-2.0+, GPL-3.0+, LGPL-3.0+
 LIBIDN_LICENSE_FILES = COPYINGv2 COPYINGv3 COPYING.LESSERv3