Fix android build

Author: m-kuhn

src/core/qgsapplication.cpp

@@ -787,6 +787,8 @@ QString QgsApplication::userFullName()
   //fall back to login name
   if ( sUserFullName.isEmpty() )
     sUserFullName = userLoginName();
+#elif defined(Q_OS_ANDROID)
+  sUserFullName = "Not available";
 #else
   struct passwd *p = getpwuid( getuid() );