qcacmn: Update wmi ready to false when the legacy cb returns error

Presently even when the ready event legacy callback fails in
creation of the pdev, the error is not propagated correctly. This
can result in accessing the invalid memory.

Check the legacy cb return status and update wmi ready status to
false in case pdev creation fails.

Change-Id: Ia4f94154357debedc94b4b20e789bff80a4047f7
CRs-Fixed: 2426611