NFC: Avoid VEN gpio toggle after boot

VEN will be toggled from NFC driver only once
during boot, after that MW shouldn't modify it's state
as eSE is also powered using VEN gpio in SN100 NFC HW.

VEN toggle will reset eSE power and cause failure if
any communication is in progress.

Change-Id: Id1c75a47017e53cc9d597e8d307a80a667207f74
Signed-off-by: Gaurav Singhal <gsinghal@codeaurora.org>