Use latest installed OpenSSL 3 as OPENSSL_NEXT

Signed-off-by: Ronald Cron <ronald.cron@arm.com>
diff --git a/tests/scripts/all.sh b/tests/scripts/all.sh
index e17d5ac..74921dc 100755
--- a/tests/scripts/all.sh
+++ b/tests/scripts/all.sh
@@ -44,7 +44,7 @@
 #     * GNUTLS_{CLI,SERV} = 3.4.10
 #     * GNUTLS_NEXT_{CLI,SERV} = 3.7.2
 #     * OPENSSL = 1.0.2g (without Debian/Ubuntu patches)
-#     * OPENSSL_NEXT = 1.1.1a
+#     * OPENSSL_NEXT = 3.1.2
 # See the invocation of check_tools below for details.
 #
 # This script must be invoked from the toplevel directory of a git
@@ -195,6 +195,10 @@
         export CC="clang"
     fi
 
+    if [ -n "${OPENSSL_3+set}" ]; then
+        export OPENSSL_NEXT="$OPENSSL_3"
+    fi
+
     # Include more verbose output for failing tests run by CMake or make
     export CTEST_OUTPUT_ON_FAILURE=1