You need to create a bbappend for the linux recipe (i.e.
"linux-raspberrypi_%.bbappend") and later override the variable "CMDLINE".
For the original content of this variable see
http://git.yoctoproject.org/cgit/cgit.cgi/meta-raspberrypi/tree/recipes-kernel/linux/linux-raspberrypi.inc
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I found cmdline.txt in a folder called bcm2835-bootfiles, so I thought
this was related to the bcm2835-bootfiles.bb recipe. I created my own
cmdline.txt and a .bbappend saying where I put it, but it didn't work.
Looking at the recipe, it doesn't mention cmdline.txt. What recipe deals
with that
