tests: add missing dependency to build QTEST_QEMU_BINARY, round 2

tests: add missing dependency to build QTEST_QEMU_BINARY, round 2

In commit b94b330e2333 ("tests: add missing dependency to build
QTEST_QEMU_BINARY", 2017-07-31), Phil fixed the dependency list of make
target "check-qtest-%". Namely, the recipe would set QTEST_QEMU_BINARY to
the softmmu emulator for the emulation target, but the prerequisites
didn't include the emulator.

The same issue affects the "check-report-qtest-%.tap" make target, which
is the other make target whose recipe sets QTEST_QEMU_BINARY:

> $ make -j4 check-report-qtest-aarch64.tap
>   TAP     check-report-qtest-aarch64.tap
> sh: /.../aarch64-softmmu/qemu-system-aarch64: No such file or directory

Apply Phil's fix to this make target too.

Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
Tested-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>