[PATCH] 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, it is a bit confusing whether the script hangs, I do not quite
know what to do next util I understand the code logic.

At the beginning, I want to print some info if no filenames are given [1],
but as Joe Perches said, this is unnecessary. It's like trying to make cat
without command line arguments emit something.

So as Lukas Bulwahn suggested, add description for somebody that actually
reads the available kernel documentation on checkpatch.

[1] https://lore.kernel.org/patchwork/patch/1429026/

Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
 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..181b95e 100644
--- a/Documentation/dev-tools/checkpatch.rst
+++ b/Documentation/dev-tools/checkpatch.rst
@@ -210,6 +210,8 @@ Available options:
 
    Display the help text.
 
+When FILE is -, or no filenames are given, read standard input.
+
 Message Levels
 ==============
 
-- 
2.1.0