components,doc,yocto/linux,oeqa: Switch to using the MHUv3 driver

Remove the previous patch on the MHUv2 driver to make it work with
MHUv3.

Update all references from MHUv2 to MHUv3.

Increase the timeout for iperf tests. The switch to the MHUv3 driver
leads to increased network performance between the Primary Compute and
the Safety Island. The iperf/zperf tests take the same time from the
point of view of the simulated components, and they are now transferring
more data in the same amount of simulated time, which leads to an
increase in test time from the point of view of the Host.
zperf doesn't allow for floating point arguments, so setting a test time
of less than a second is not an option.

Signed-off-by: Ambroise Vincent <ambroise.vincent@arm.com>