Add sample service and target for system reset

Added sample target and service file for system reset target. Each
platform can provide their own service file for system reset target.

Signed-off-by: Vijay Khemka <vijaykhemka@fb.com>
Change-Id: Id53b2cd542c306701237b93c4a6f58d86d21ca2c
diff --git a/power-control-x86/service_files/chassis-system-reset.target b/power-control-x86/service_files/chassis-system-reset.target
new file mode 100644
index 0000000..2d19fe3
--- /dev/null
+++ b/power-control-x86/service_files/chassis-system-reset.target
@@ -0,0 +1,2 @@
+[Unit]
+Description=System unit to hard reset or system reset chassis