Revert "x86: add support for Mellanox Spectrum SN2000 Switches"

Revert "x86: add support for Mellanox Spectrum SN2000 Switches"

This reverts commit 3004c20614fdb29732f750417a578274a8ed988e.

The commit added the needed packages for the new target
to the generic x86_64 image. This results into unwanted
modules and firmware files for other x86 devices.

Additionally, there is the following error message
while booting the image on other x86 devices:
[    8.531720] kmodloader: 1 module could not be probed
[    8.532613] kmodloader: - leds-mlxcpld - 0

For now, the needed packages will have to be selected
manually while configuring the image.

Signed-off-by: Til Kaiser <til.kaiser@gmx.de>