gpio: tools: add .gitignore for generated files

Add .gitignore for generated files.

Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
[Dropped include dir]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/tools/gpio/.gitignore b/tools/gpio/.gitignore
new file mode 100644
index 0000000..9e9dd4b
--- /dev/null
+++ b/tools/gpio/.gitignore
@@ -0,0 +1,4 @@
+gpio-event-mon
+gpio-hammer
+lsgpio
+