tools/power/acpi: Add .gitignore file

Add a .gitignore file so that git commands do not pick up the resulting
binaries and directories.

Signed-off-by: Prarit Bhargava <prarit@redhat.com>
Acked-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/tools/power/acpi/.gitignore b/tools/power/acpi/.gitignore
new file mode 100644
index 0000000..cba3d99
--- /dev/null
+++ b/tools/power/acpi/.gitignore
@@ -0,0 +1,4 @@
+acpidbg
+acpidump
+ec
+include