free NULL cleanup

This commit handles BIO_ACCEPT_free BIO_CB_FREE BIO_CONNECT_free
BIO_free BIO_free_all BIO_vfree

Reviewed-by: Matt Caswell <matt@openssl.org>

apps/ecparam.c

diff --git a/apps/ecparam.c b/apps/ecparam.c
index 06ac77b..d417747 100644
--- a/apps/ecparam.c
+++ b/apps/ecparam.c
@@ -621,10 +621,8 @@
         BN_free(ec_cofactor);
     if (buffer)
         OPENSSL_free(buffer);
-    if (in != NULL)
-        BIO_free(in);
-    if (out != NULL)
-        BIO_free_all(out);
+    BIO_free(in);
+    BIO_free_all(out);
     if (group != NULL)
         EC_GROUP_free(group);
     apps_shutdown();