gnutls: Added configuration option to use external libtasn1

Signed-off-by: Nikos Mavrogiannopoulos <nmav@gnutls.org>

libs/gnutls/Config.in

@@ -31,4 +31,8 @@ config GNUTLS_PSK
 config GNUTLS_ANON
 	bool "enable anonymous authentication support"
 
+config GNUTLS_EXT_LIBTASN1
+	bool "use external libtasn1"
+	default n
+
 endmenu

libs/gnutls/Makefile

@@ -75,7 +75,7 @@ endef
 define Package/libgnutls
 $(call Package/gnutls/Default)
   TITLE+= (library)
-  DEPENDS+= +libnettle +!LIBNETTLE_MINI:libgmp
+  DEPENDS+= +libnettle +!LIBNETTLE_MINI:libgmp +GNUTLS_EXT_LIBTASN1:libtasn1
 endef
 
 define Package/libgnutls/description
@@ -102,7 +102,6 @@ CONFIGURE_ARGS+= \
 	--disable-guile \
 	--disable-nls \
 	--without-zlib \
-	--with-included-libtasn1 \
 	--enable-local-libopts \
 	--disable-doc \
 	--disable-tests \
@@ -110,6 +109,10 @@ CONFIGURE_ARGS+= \
 	--disable-crywrap \
 	--without-p11-kit
 
+ifneq ($(CONFIG_GNUTLS_EXT_LIBTASN1),y)
+CONFIGURE_ARGS += --with-included-libtasn1
+endif
+
 ifeq ($(CONFIG_LIBNETTLE_MINI),y)
 CONFIGURE_ARGS += --with-nettle-mini
 endif