doc: Documentation updates

Primary updates included in this patch:

* Consistently use passive voice in documentation
* Remove K3s usage instructions, instead relying on upstream project
* Update yoctoproject documentation version
* Update EWAOL overview 'major features'

Issue-Id: SCM-3893
Signed-off-by: Richard Neill <richard.neill@arm.com>
Change-Id: I327d87d2e346b98debd8d854462bfd549d6d3eae