LEDS: Add systemd unit to call led-set-all-groups-asserted.sh

led-set-all-groups-asserted.sh needs to be called with "false"
as part of below transitions to turn off all indicator LEDs
- BMC booting to standby and staying at standby
- BMC starting to power on

Change-Id: I62bf5aa96173df267d60023fab2190c559610157
Signed-off-by: Vishwanatha Subbanna <vishwa@linux.vnet.ibm.com>
diff --git a/recipes-phosphor/leds/phosphor-led-manager/obmc/led/set-all/groups/config b/recipes-phosphor/leds/phosphor-led-manager/obmc/led/set-all/groups/config
new file mode 100644
index 0000000..664200d
--- /dev/null
+++ b/recipes-phosphor/leds/phosphor-led-manager/obmc/led/set-all/groups/config
@@ -0,0 +1 @@
+EXCLUDED_GROUPS=bmc_booted power_on