meta-quanta-q71l: phosphor: sensors: add missing inherit

This recipe uses compose_list which is defined in the
obmc-phosphor-utils class.

Fixes: openbmc/openbmc#3088

Change-Id: I7450bbc1dc44915c784459e78d26e8836785ca7b
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/meta-quanta/meta-q71l/recipes-phosphor/sensors/phosphor-hwmon%.bbappend b/meta-quanta/meta-q71l/recipes-phosphor/sensors/phosphor-hwmon%.bbappend
index c2805af..19365c2 100644
--- a/meta-quanta/meta-q71l/recipes-phosphor/sensors/phosphor-hwmon%.bbappend
+++ b/meta-quanta/meta-q71l/recipes-phosphor/sensors/phosphor-hwmon%.bbappend
@@ -1,3 +1,5 @@
+inherit obmc-phosphor-utils
+
 FILESEXTRAPATHS_prepend_quanta-q71l := "${THISDIR}/${PN}:"
 
 # More conf files can be added as sensors are added.