doc: add MSR_IA32_TSX_CTRL snapshot limitation
doc: add MSR_IA32_TSX_CTRL snapshot limitation

Signed-off-by: Nikita Kalyazin <c53e872bee32dfab6176fca8e0f6635ed7a871db@amazon.co.uk>

firecracker-microvm/firecracker,firecracker-microvm/firecracker,firecracker-microvm/firecracker,firecracker-microvm/firecracker,firecracker-microvm/firecracker