checkincludes.pl: add option to remove duplicates in place

checkincludes.pl is more useful if it actually removed the lines.  This
adds support for that with -r.

[[email protected]: improve usage message]
Signed-off-by: Luis R. Rodriguez <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Sam Ravnborg <[email protected]>
1 file changed