readosm had an extra license field, fixed

extra license introduced at 8488d133f37d6f6e2ab0b13e9513af28ddb8da6e

pkgs/development/libraries/readosm/default.nix

···
   meta = {
     description = "An open source library to extract valid data from within an Open Street Map input file";
     homepage = https://www.gaia-gis.it/fossil/readosm;
-    license = [ "GPLv2+" "LGPLv2+" "MPL1.1" ];
     license = with stdenv.lib.licenses; [ mpl11 gpl2Plus lgpl21Plus ];
   };
 }