regulators: Add/install base service

Create a service file to start the phosphor-regulators binary that will
be linked to the multi-user target so that its started at BMC standby.
Add this service file to be installed within the systemd services
directory(`/lib/systemd/system/`).

Change https://gerrit.openbmc-project.xyz/27972 installs the binary

Tested:
    Service file installed in /lib/systemd/system/
    Linked to multi-user target in recipe and it started at BMC standby

Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
Change-Id: I5ef1485569ada2737e0e8d5ce11965c4eff0eb45
diff --git a/services/phosphor-regulators.service b/services/phosphor-regulators.service
new file mode 100644
index 0000000..a7680dc
--- /dev/null
+++ b/services/phosphor-regulators.service
@@ -0,0 +1,11 @@
+[Unit]
+Description=Phosphor Power Regulators Daemon
+Wants=obmc-mapper.target
+After=obmc-mapper.target
+
+[Service]
+Restart=on-failure
+ExecStart=/usr/bin/phosphor-regulators
+
+[Install]
+WantedBy=multi-user.target