ovsdb-idlc: Use ALIGNED_CAST to avoid spurious warnings for index rows.

The *_index_init_row() function casts a generic ovsdb_idl_row pointer to
a specific type of row pointer.  This can cause an increase in required
alignment with some kinds of data on some architectures.  GCC complains,
e.g.:

    lib/vswitch-idl.c: In function 'ovsrec_flow_sample_collector_set_index_init_row'
    lib/vswitch-idl.c:9277:12: warning: cast increases required alignment of target

However, rows are always allocated with malloc(), which returns member
suitable for any type, so this is a false positive warning and this commit
suppresses it.

Signed-off-by: Ben Pfaff <[email protected]>
Acked-by: Han Zhou <[email protected]>

ovsdb/ovsdb-idlc.in

@@ -1217,7 +1217,7 @@ struct %(s)s *
 %(s)s_index_init_row(struct ovsdb_idl_index *index)
 {
     ovs_assert(index->table->class_ == &%(p)stable_%(tl)s);
-    return (struct %(s)s *) ovsdb_idl_index_init_row(index);
+    return ALIGNED_CAST(struct %(s)s *, ovsdb_idl_index_init_row(index));
 }
 
 struct %(s)s *