BUILD/MINOR: ssl: Fix compilation with SSL enabled

The CA/CRL hot update patches did not compile on some targets of the CI
(mainly gcc + ssl). This patch should fix almost all of them. It adds
missing variable initializations and return value checks to the
BIO_reset calls in show_crl_detail.
diff --git a/src/ssl_sock.c b/src/ssl_sock.c
index c7e1005..ec271c9 100644
--- a/src/ssl_sock.c
+++ b/src/ssl_sock.c
@@ -319,7 +319,7 @@
 /* mimic what X509_STORE_load_locations do with store_ctx */
 static int ssl_set_cert_crl_file(X509_STORE *store_ctx, char *path)
 {
-	X509_STORE *store;
+	X509_STORE *store = NULL;
 	struct cafile_entry *ca_e = ssl_store_get_cafile_entry(path, 0);
 	if (ca_e)
 		store = ca_e->ca_store;