Change docstring to be more accurate

Author: makermelissa

adafruit_platformdetect/__init__.py

@@ -136,7 +136,7 @@ def check_board_asset_tag_value(self):
 
     def check_board_name_value(self):
         """
-        Search /sys/devices/virtual/dmi/id for the device model and return its value, if found,
+        Search /sys/devices/virtual/dmi/id for the board name and return its value, if found,
         otherwise None. Debian/ubuntu based
         """
         board_name = None