tests/qtest/bios-tables-test: Use MiB macro rather hardcode value

Replace 1024 * 1024 with MiB macro.

Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Message-Id: <20250520130158.767083-4-maobibo@loongson.cn>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
1 file changed