package/opkg: enable sha256sum support

Support for sha256 has no additional dependency, the size increase is
minimal, and sha256 is the smallest hash still not broken (md5 and sha1
are), so it makes sense to enable it unconditionally.

Signed-off-by: Adam Duskett <adam.duskett@amarulasolutions.com>
[yann.morin.1998@free.fr: make it unconditional and commit log]
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

package/opkg/opkg.mk

@@ -10,6 +10,7 @@ OPKG_DEPENDENCIES = host-pkgconf libarchive
 OPKG_LICENSE = GPL-2.0+
 OPKG_LICENSE_FILES = COPYING
 OPKG_INSTALL_STAGING = YES
+OPKG_CONF_OPTS = --enable-sha256
 
 ifeq ($(BR2_PACKAGE_OPKG_GPG_SIGN),y)
 OPKG_CONF_OPTS += --enable-gpg