Enable UEFI & TMP2 without enforcing Secure Boot

[nazarewk]

This is a feature request spin-off from #5996 .

It would be great to have a Secure Boot switch separate (it's ok to still be enabled by default) from TPM 2.0 Device option, so it's possible to turn it off.

My use cases involve:

• deploying a Linux machine using TPM2.0 device for full-disk-encryption without Secure Boot in place
  • possibly testing the transition between those 2 modes in future
• booting Linux ISOs in above use case (same as Enabling TPM 2.0 device prevents booting off ISO #5996)

[osy]

You can disable Secure Boot from UEFI settings (press Esc when booting).

[nazarewk]

You can disable Secure Boot from UEFI settings (press Esc when booting).

this indeed works, should probably be added to documentation of UTM for people having no background in UTM/UEFI VMs like myself