checkpatch: allow not using -f with files that are in git

If a file exists in git and checkpatch is used without the -f flag for
scanning a file, then checkpatch will scan the file assuming it's a patch
and emit:

ERROR: Does not appear to be a unified-diff format patch

Change the behavior to assume the -f flag if the file exists in git.

[[email protected]: fix git "fatal" warning if file argument outside kernel tree]
  Link: https://lkml.kernel.org/r/[email protected]

Signed-off-by: Joe Perches <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Reviewed-by: Julia Lawall <[email protected]>
Cc: Rasmus Villemoes <[email protected]>
Link: https://lkml.kernel.org/r/[email protected]
Signed-off-by: Linus Torvalds <[email protected]>

0 files changed, 0 insertions, 0 deletions