package/libcoap: doesn't build with libressl

Fix the following build failure with libressl raised since commit
8b14f6b49b962d4d8f7135d85afa15658ea8f94b:

src/coap_openssl.c:107:3: erreur: nom de type « BIO_ADDR » inconnu
  107 |   BIO_ADDR *bio_addr;
      |   ^~~~~~~~

Fixes:
 - http://autobuild.buildroot.org/results/30022e437f349459994dccfb612773d529d97a20

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
(cherry picked from commit 0796c878f4c9ad786a6c4c4716e4239fa070cd73)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>

package/libcoap/libcoap.mk

@@ -18,7 +18,7 @@ ifeq ($(BR2_PACKAGE_GNUTLS),y)
 LIBCOAP_DEPENDENCIES += gnutls
 LIBCOAP_CONF_OPTS += \
 	--enable-dtls --with-gnutls --without-mbedtls --without-openssl
-else ifeq ($(BR2_PACKAGE_OPENSSL),y)
+else ifeq ($(BR2_PACKAGE_LIBOPENSSL),y)
 LIBCOAP_DEPENDENCIES += openssl
 LIBCOAP_CONF_OPTS += \
 	--enable-dtls --without-gnutls --without-mbedtls --with-openssl