msm: pm2: Raise SPI interrupt instread of SGI to non boot CPUs

Once APPS comes out of PC and mpdecision want to bring the non-boot
cpus to online, first CORE0 raises the SPI interrupt(MPCORE) to bring
the cores(1/2/3) online. While bringing the cores online, CORE0 raises
the SPI interrupt instead of SGI. Because once APPS does a PC QGIC
looses its state and none of the non-boot cpus are not capable of
receiving the SGI interrupt until cores configure the QGIC PPIs&SGIs
by themselves.

Change-Id: Ic4aedeffbcd3fa2f0aa15e2e8ed7e25a03468f87
Signed-off-by: Murali Nalajala <mnalajal@codeaurora.org>