Fix coverity issues CID 1457745...1457752, 1457853, 1457854

CID 1457854 - keymgmt_lib.c : OVERRUN
CID 1457853 - self_test_kats.c : UNINT
CID 1457752 - fipsprov.c RESOURCE_LEAK (code change in another PR removed this)
CID 1457751 - apps/pkcs12.c CHECKED_RETURN
CID 1457750 - dsa_ossl.c RESOURCE_LEAK (marked as false positive since tmp can not be NULL)
CID 1457749 - apps/nseq.c : CHECKED_RETURN
CID 1457748 - cipher_aes_cbc_hmac_sha.c : SIZEOF_MISMATCH
CID 1457747 - cipher_aes_cbc_hmac_sha.c : SIZEOF_MISMATCH
CID 1457746 - same as 1457752
CID 1457745 - apps/ocsp  : CHECKED_RETURN

Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/10934)

apps/nseq.c

diff --git a/apps/nseq.c b/apps/nseq.c
index 5b7ab67..9d1e095 100644
--- a/apps/nseq.c
+++ b/apps/nseq.c
@@ -82,8 +82,10 @@
         seq->certs = sk_X509_new_null();
         if (seq->certs == NULL)
             goto end;
-        while ((x509 = PEM_read_bio_X509(in, NULL, NULL, NULL)))
-            sk_X509_push(seq->certs, x509);
+        while ((x509 = PEM_read_bio_X509(in, NULL, NULL, NULL))) {
+            if (!sk_X509_push(seq->certs, x509))
+                goto end;
+        }
 
         if (!sk_X509_num(seq->certs)) {
             BIO_printf(bio_err, "%s: Error reading certs file %s\n",