docs: kernel-parameters.txt: Fix broken references

Fix remaining broken references in kernel-parameters.txt.

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Jimmy Assarsson <jimmyassarsson@gmail.com>
Link: https://lore.kernel.org/r/20200402172614.3020-2-jimmyassarsson@gmail.com


Signed-off-by: Jonathan Corbet <corbet@lwn.net>