The .ifs file is good for QEMU, just pass it in as the kernel. Here's the qemu command I use to startup a qemu running 
QNX where arm.ifs is the .ifs file you have built.

qemu-system-arm -machine vexpress-a15 -cpu cortex-a15 -m 1G -kernel arm.ifs  -nographic -serial mon:stdio

You will need to ensure that your build file builds the correct type of ifs:
[image=0x80000000]
[virtual=armle-v7,elf +compress] boot = {
    startup-armv8_fm
    PATH=/proc/boot:/sbin:/bin:/usr/bin:/usr/sbin LD_LIBRARY_PATH=/proc/boot:/lib:/usr/lib:/lib/dll:/lib/dll/pci 
CONFIG_PATH=/proc/boot:/etc procnto-smp-instr
}

I also have an fs built in to a qcow image running on a virtio block driver and a virtio network driver with these 
additional options on the qemu command line:

-drive file=armfs.qcow2,if=none,id=drv0 -device virtio-blk-device,drive=drv0 -netdev bridge,br=virbr0,id=net0 -device 
virtio-net-device,netdev=net0,mac=$MACADDR

Note that the startup-armv8_fm and virtio drivers are part of the virtio extras package in SDP7.0.0 and not part of the 
base SDP7 install.