build: Update render node enable instructions

Render nodes were not getting enabled when setting up a newly installed
14.10 Ubuntu system. To get the rnodes=1 option to work it is necessary
to update the ramfs boot image.

1 files changed, 2 insertions, 0 deletions

diff --git a/BUILD.md b/BUILD.md
index 1a79451b..19b11c77 100644
--- a/BUILD.md
+++ b/BUILD.md
@@ -63,6 +63,8 @@ sudo tee /etc/modprobe.d/drm.conf << EOF
 # Enable render nodes
 options drm rnodes=1
 EOF
+# this will add the rnodes=1 option into the boot environment
+sudo update-initramfs -k all -u
 ```
 ```
 sudo tee /etc/udev/rules.d/drm.rules << EOF