ntfs-3g: fix build with encryption support

Fixes http://autobuild.buildroot.org/results/4baa45ca1f4804be1a76a69bb8158c6a91d96d6b/

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

package/ntfs-3g/ntfs-3g.mk

@@ -21,6 +21,7 @@ ifeq ($(BR2_PACKAGE_UTIL_LINUX_LIBUUID),y)
 endif
 
 ifeq ($(BR2_PACKAGE_NTFS_3G_ENCRYPTED),y)
+	NTFS_3G_CONF_ENV += LIBGCRYPT_CONFIG=$(STAGING_DIR)/usr/bin/libgcrypt-config
 	NTFS_3G_CONF_OPT += --enable-crypto
 	NTFS_3G_DEPENDENCIES += gnutls
 endif