regs: Add/install config service

Create a service file to call a method within the phosphor-regulators
binary to configure the regulators. Add this service file to be
installed within the systemd services directory(`/lib/systemd/system/`).

Tested:
    Started before pre-poweron target is set
    Keeps next poweron target from starting until completes

Signed-off-by: Matthew Barth <msbarth@us.ibm.com>
Change-Id: I1c470c7221c589733e6cb5bb8346545e2039d467
diff --git a/meson.build b/meson.build
index 2bc4b50..6a1dc6d 100644
--- a/meson.build
+++ b/meson.build
@@ -48,7 +48,8 @@
     'pseq-monitor-pgood.service',
     'pseq-monitor.service',
     'phosphor-psu-monitor.service',
-    'phosphor-regulators.service'
+    'phosphor-regulators.service',
+    'phosphor-regulators-config.service'
 ]
 
 foreach service : services