[PATCH docs] cheatsheet.md: Re-write QEMU invocation example

[OpenBMC Patches]

The commandline provided had several issues:

* The -dtb option was redundant as we boot with the cuImage, and caused
  some kernel configuration to be skipped which in turn ended in a
  kernel panic
* -append argument was redundant with respect to the devicetree
* The file paths used typically required the user to change up out of
  the build directory after bitbaking obmc-phosphor-image

The patch addresses all of the above.

Signed-off-by: Andrew Jeffery <andrew at aj.id.au>

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https://github.com/openbmc/docs/pull/27

Andrew Jeffery (1):
  cheatsheet.md: Re-write QEMU invocation example

 cheatsheet.md | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

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2.8.4