binderfs: add gitignore for generated sample program

Let's keep "git status" happy and quiet.

Fixes: 9762dc1432e1 ("samples: add binderfs sample program
Fixes: fca5e94921d5 ("samples: binderfs: really compile this sample and fix build issues")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 file changed