MLK-20308 sound:asoc: fix re-enablement bug

MLK-20308 sound:asoc: fix re-enablement bug

When hwvad is enabled, if you try to re-enable it again, it should fail.
However, we were also double setting state to OFF on fail, which is
wrong because it resets the state and allows the second retry to enable
even if it wasn't disabled before.
Now we only return EBUSY.

Reviewed-by: Daniel Baluta <daniel.baluta@nxp.com>
Signed-off-by: Cosmin-Gabriel Samoila <cosmin.samoila@nxp.com>
(cherry picked from commit 1ef8c4696c0b0c1e4a0f384dd7300d4dab293f3b)