power: smb1390: remove unnecessary votables

Votable pl_disable is used to make sure in SW level only one secondary
charger active at one time if multiple are present. However, this is
the way HW works.

Another votable hvdcp_hw_inov_dis_votable is also useless in SM1850
because SW INOV is always the choice.

Drop both votables.

Change-Id: I8ba9bc7a897c3245ac556a4a474113b247faaf27
Signed-off-by: Harry Yang <harryy@codeaurora.org>