kvm add solution message for when user needs to reload the terminal to get libvirt permissions

[medyagh]

when user adds their user to the libvir group, they still need to reload the terminal,

$ /snap/google-cloud-sdk/current/bin/minikube start --driver=kvm2
😄  minikube v1.16.0 on Ubuntu 20.10
✨  Using the kvm2 driver based on user configuration

💣  Exiting due to PROVIDER_KVM2_ERROR: /usr/bin/virsh domcapabilities --virttype kvm failed:
error: failed to connect to the hypervisor
error: Failed to connect socket to '/var/run/libvirt/libvirt-sock': Permission denied
💡  Suggestion: Follow your Linux distribution instructions for configuring KVM
📘  Documentation: https://minikube.sigs.k8s.io/docs/reference/drivers/kvm2/

minikube should instead of that error, give users Advice that Might help if we get that specific error

https://github.com/medyagh/minikube/blob/199ea3425b8343e533d8d1982ad750a8dab7d59e/pkg/minikube/reason/known_issues.go#L1003

additional information @spowelljr

$ virt-host-validate
  QEMU: Checking for hardware virtualization                                 : PASS
  QEMU: Checking if device /dev/kvm exists                                   : PASS
  QEMU: Checking if device /dev/kvm is accessible                            : FAIL (Check /dev/kvm is world writable or you are in a group that is allowed to access it)
  QEMU: Checking if device /dev/vhost-net exists                             : PASS
  QEMU: Checking if device /dev/net/tun exists                               : PASS
  QEMU: Checking for cgroup 'cpu' controller support                         : PASS
  QEMU: Checking for cgroup 'cpuacct' controller support                     : PASS
  QEMU: Checking for cgroup 'cpuset' controller support                      : PASS
  QEMU: Checking for cgroup 'memory' controller support                      : PASS
  QEMU: Checking for cgroup 'devices' controller support                     : PASS
  QEMU: Checking for cgroup 'blkio' controller support                       : PASS
  QEMU: Checking for device assignment IOMMU support                         : PASS
  QEMU: Checking if IOMMU is enabled by kernel                               : WARN (IOMMU appears to be disabled in kernel. Add intel_iommu=on to kernel cmdline arguments)
  QEMU: Checking for secure guest support                                    : WARN (Unknown if this platform has Secure Guest support)
   LXC: Checking for Linux >= 2.6.26                                         : PASS
   LXC: Checking for namespace ipc                                           : PASS
   LXC: Checking for namespace mnt                                           : PASS
   LXC: Checking for namespace pid                                           : PASS
   LXC: Checking for namespace uts                                           : PASS
   LXC: Checking for namespace net                                           : PASS
   LXC: Checking for namespace user                                          : PASS
   LXC: Checking for cgroup 'cpu' controller support                         : PASS
   LXC: Checking for cgroup 'cpuacct' controller support                     : PASS
   LXC: Checking for cgroup 'cpuset' controller support                      : PASS
   LXC: Checking for cgroup 'memory' controller support                      : PASS
   LXC: Checking for cgroup 'devices' controller support                     : PASS
   LXC: Checking for cgroup 'freezer' controller support                     : PASS
   LXC: Checking for cgroup 'blkio' controller support                       : PASS
   LXC: Checking if device /sys/fs/fuse/connections exists                   : PASS
$ virsh -c qemu:///system list --all
error: failed to connect to the hypervisor
error: Failed to connect socket to '/var/run/libvirt/libvirt-sock': Permission denied
$ virsh net-list
error: failed to connect to the hypervisor
error: Failed to connect socket to '/var/run/libvirt/libvirt-sock': Permission denied

[prezha]

/assign