ARM: dts: msm: Allow spmi-arb interrupts to wakeup device for mdm9640

Remove the 'qcom,not-wakeup' flag from the mdmcalifornium device
tree to allow spmi-arb interrupts to be wakeup capable.

CRs-Fixed: 1053671
Change-Id: Ie412c3235e7e45d55bb28255d11db03082b94691
Signed-off-by: Devesh Jhunjhunwala <deveshj@codeaurora.org>