lkdtm: clean up after rename

This cleans up comments a bit to improve readability, adjusts the
name of the module after the source file renaming, and corrects the
MAINTAINERS for the upcoming lkdtm files.

Signed-off-by: Kees Cook <keescook@chromium.org>
diff --git a/MAINTAINERS b/MAINTAINERS
index 2ebe195..977504e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -6954,7 +6954,7 @@
 LINUX KERNEL DUMP TEST MODULE (LKDTM)
 M:	Kees Cook <keescook@chromium.org>
 S:	Maintained
-F:	drivers/misc/lkdtm.c
+F:	drivers/misc/lkdtm*
 
 LLC (802.2)
 M:	Arnaldo Carvalho de Melo <acme@ghostprotocols.net>