dis_ucode_ldr was introduced in 65cef131 ("x86, microcode: Add a disable
chicken bit") and will disable microcode loading on x86.  This kernel
parameter is buried in the code and should be added to the Documentation.
Signed-off-by: NPrarit Bhargava <prarit@redhat.com>
Signed-off-by: NJonathan Corbet <corbet@lwn.net>