hwmonio: add underscore prefix to members

Add underscore prefix to members for hwmonio object.

Change-Id: Iab5aed5ddba3b1793bb16b0f1501a11ff95b7f35
Signed-off-by: Patrick Venture <venture@google.com>
diff --git a/hwmonio.hpp b/hwmonio.hpp
index 902888f..f0c7248 100644
--- a/hwmonio.hpp
+++ b/hwmonio.hpp
@@ -107,7 +107,7 @@
     std::string path() const override;
 
   private:
-    std::string p;
+    std::string _p;
 };
 } // namespace hwmonio