idt_test in ubuntu_kvm_unit_test timeout with J-realtime on openstack AMD64

[Po-Hsu Lin]

idt_test test in ubuntu_kvm_unit_test will timeout with J-realtime on openstack amd64 instance. This issue can be seen after we start testing on openstack with 5.15.0-1036.39 in sru-20230320.

Test log:
 Running '/home/ubuntu/autotest/client/tmp/ubuntu_kvm_unit_tests/src/kvm-unit-tests/tests/idt_test'
 BUILD_HEAD=d8edb59a
 timeout -k 1s --foreground 90s /usr/bin/qemu-system-x86_64 --no-reboot -nodefaults -device pc-testdev -device isa-debug-exit,iobase=0xf4,iosize=0x4 -vnc none -serial stdio -device pci-testdev -machine accel=tcg -kernel /tmp/tmp.aG8YXO0HgF -smp 1 # -initrd /tmp/tmp.uLQLbV1wkB
 enabling apic
 smp: waiting for 0 APs
 Starting IDT test
 qemu-system-x86_64: terminating on signal 15 from pid 11635 (timeout)
 FAIL idt_test (timeout; duration=90s)

This issue still exist with the latest upstream kvm-unit-tests code (02d8befe99f8)
It's worthy to note that this test has passed with j/ibm on openstack amd64.