doc: fix broken references

There are numerous broken references to Documentation files (in other
Documentation files, in comments, etc.). These broken references are
caused by typo's in the references, and by renames or removals of the
Documentation files. Some broken references are simply odd.

Fix these broken references, sometimes by dropping the irrelevant text
they were part of.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

Documentation/virtual/lguest/lguest.c

@@ -436,7 +436,7 @@ static unsigned long load_bzimage(int fd)
 
 	/*
 	 * Go back to the start of the file and read the header.  It should be
-	 * a Linux boot header (see Documentation/x86/i386/boot.txt)
+	 * a Linux boot header (see Documentation/x86/boot.txt)
 	 */
 	lseek(fd, 0, SEEK_SET);
 	read(fd, &boot, sizeof(boot));