linux-wandboard

ENGR00274478 fix gpu memory multi-lock failure

this issue cause system boot with multi-user switch on JB4.3,

root cause is gpu memory cannot be multi-locked in same process,
gpu memory lock reference is added to allow multi-lock in kernel driver.

Signed-off-by: Xianzhong <b07117@freescale.com>
Acked-by: Jason Liu