sensor.envirophat: add missing requirement (#7451)

Adding requirements that is not explicitly pulled in by the library
that manages the Enviro pHAT.

homeassistant/components/sensor/envirophat.py

@@ -15,7 +15,8 @@ import homeassistant.helpers.config_validation as cv
 from homeassistant.helpers.entity import Entity
 from homeassistant.util import Throttle
 
-REQUIREMENTS = ['envirophat==0.0.6']
+REQUIREMENTS = ['envirophat==0.0.6',
+                'smbus-cffi==0.5.1']
 
 _LOGGER = logging.getLogger(__name__)
 

requirements_all.txt

@@ -767,6 +767,9 @@ sleekxmpp==1.3.2
 # homeassistant.components.sleepiq
 sleepyq==0.6
 
+# homeassistant.components.sensor.envirophat
+smbus-cffi==0.5.1
+
 # homeassistant.components.media_player.snapcast
 snapcast==1.2.2