Boot USB memstick with MBR (WAS: Re: [RFC] Deprecation and removal of the drm2 driver)

[Philip Homburg]

I tried both FreeBSD-11.2-BETA2-amd64-bootonly.iso.xz and 
FreeBSD-11.2-BETA2-amd64-mini-memstick.img.xz on a Dell PowerEdge 2950 
BIOS version 2.7.0. With both images, the USB stick is not recognized.

For reference I tried an image for a random other OS and in that case the
USB stick is recognized.

I'll try to experiment a bit to see if I can find what causes the issue.