[PATCH v3] Documentation: checkpatch: add description if no filenames are given

[Tiezhu Yang]

After commit 45107ff6d526 ("checkpatch: if no filenames then read stdin"),
if no filenames are given, it will read patch from stdin rather than exit
directly. This means the script waits for input indefinitely, which
confuses new checkpatch users at first.

Add some basic documentation on this behaviour of checkpatch to lower
the confusion.

Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---

v3: Update the commit message, thank you Lukas.

 Documentation/dev-tools/checkpatch.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/dev-tools/checkpatch.rst b/Documentation/dev-tools/checkpatch.rst
index 51fed1b..3eb9ead 100644
--- a/Documentation/dev-tools/checkpatch.rst
+++ b/Documentation/dev-tools/checkpatch.rst
@@ -22,6 +22,8 @@ Usage::
 
   ./scripts/checkpatch.pl [OPTION]... [FILE]...
 
+When FILE is -, or absent, checkpatch reads from standard input.
+
 Available options:
 
  - -q,  --quiet
-- 
2.1.0