motr/m0kv: Initialize m0_idx_op with zeroes in index_op
When ENF_META flag was not used, m0_idx_op::in_attr was not properly
initialized.  Which lead to precondition check failure when trying to
run PUT KV with m0kv.
@@ -196,7 +196,7 @@ static int index_op(struct m0_realm *parent,
struct m0_bufvec *keys,
struct m0_bufvec *vals)
{
- struct m0_idx idx;
+ struct m0_idx idx = {};
struct m0_op *op = NULL;
int32_t *rcs;
int rc;
