DAOS-16078 common: fix a Coverity issue (release/2.6 catching up with…

… the master) (#14755)

This also reverts commits 3af8340 and c394274.

Signed-off-by: Jan Michalski <[email protected]>

src/common/btree.c

@@ -512,7 +512,6 @@ hkey_int_gen(d_iov_t *key,  void *hkey)
 	 * this is a little nicer to read.
 	 */
 	*(uint64_t *)hkey = 0;
-	D_ASSERT(key->iov_buf != NULL);
 	memcpy(hkey, key->iov_buf, key->iov_len);
 }
 
@@ -987,7 +986,7 @@ btr_embedded_create_hash(struct btr_context *tcx, bool force)
 			D_ERROR("Failed to get key from embedded record: " DF_RC "\n", DP_RC(rc));
 			return rc;
 		}
-		D_ASSERT(rec != NULL);
+		D_ASSERT(old_key.iov_buf != NULL);
 		btr_hkey_gen(tcx, &old_key, &rec->rec_hkey[0]);
 		btr_embedded_hash_set(tcx);
 	}