Add pressure to unit list

Pressure has been added into the Sensor interface so add it here.

Signed-off-by: Rashmica Gupta <rashmica.g@gmail.com>
Change-Id: I84a06e1b1ba0a9b78b7ac5a833fc997d16c978cb
diff --git a/virtualSensor.cpp b/virtualSensor.cpp
index 7ee3fae..f0a456c 100644
--- a/virtualSensor.cpp
+++ b/virtualSensor.cpp
@@ -348,7 +348,8 @@
     {"power", ValueIface::Unit::Watts},
     {"energy", ValueIface::Unit::Joules},
     {"utilization", ValueIface::Unit::Percent},
-    {"airflow", ValueIface::Unit::CFM}};
+    {"airflow", ValueIface::Unit::CFM},
+    {"pressure", ValueIface::Unit::Pascals}};
 
 void VirtualSensors::createVirtualSensors()
 {