[arch-general] [dkms] Don't load blacklisted modules when starting dkms.service

[Simon Brulhart]

Hello,

I found that when starting the dkms service, every dkms module is loaded
right after, even the ones that are blacklisted.
The behavior is avoidable by adding the '-b' option to modprobe, in the
dkms start script (/usr/lib/systemd/scripts/dkms), line 26.
I don't see any drawback in adding this option, and the resulting
behavior seems more intuitive in my option.

It would also help prevent some issues as the one described here:
https://bbs.archlinux.org/viewtopic.php?id=189032
Basically when using bumblebee and nvidia-dkms, the dkms service loads
the nvidia and nvidia_uvm module after bumblebeed starts, which powers
the discrete graphic card back on indefinitely.

I wasn't sure if I should directly post an issue on the bugtracker, or
first discuss about it here.

Cheers
Simon