ODROID-C1 installation to SD card

[Jared McNeill <jmcneill%invisible.ca@localhost>]

I committed a driver for the ODROID-C1 SD/MMC controller today and added 
some installation instructions on the wiki.

Unfortunately, the ODROID-C1 primary bootloader occupies the same location 
as the NetBSD disklabel, so the install process is a bit different than 
other NetBSD/evbarm boards.

https://wiki.netbsd.org/ports/evbarm/odroid-c1/