x86: Add queensbay fsp patch information in README.x86

The FSP release version 001 for Intel Queensbay has a bug which
could cause random endless loop during the FspInit call. This bug
was published by Intel although Intel did not describe any details.
Describe this information in the x86 doc so that U-Boot Queensbay
support is invulnerable.

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Acked-by: Simon Glass <sjg@chromium.org>