Dialer: OpenStreetMap: It knows case-insensitivity now!

We don't need to build a regex with all capital and lowercase letters
of the user input, just specify case-insensitivity to the query!

Source: 
https: //wiki.openstreetmap.org/wiki/Overpass_API/Overpass_QL#Case_insensitively
Change-Id: Ib59b2f24a72b824ddf4c4f6388da2a4cdfab3fd6