There is actually a word that describes precisely this type of chitchat: you're looking for the word phatic.
phat·ic /ˈfatik/ adj.
denoting or relating to language used for general purposes of social interaction, rather than to convey information or ask questions. Utterances such as hello, how are you? and nice morning, isn't it? are phatic.
(From Oxford Dictionaries Online, my emphasis)
