Turn some license strings into lib.licenses values

pkgs/development/misc/avr8-burn-omat/default.nix

@@ -27,6 +27,6 @@ stdenv.mkDerivation {
   meta = { 
     description = "GUI tool for avrdude";
     homepage = http://avr8-burn-o-mat.brischalle.de/avr8_burn_o_mat_avrdude_gui_en.html;
-    license = "GPLv3";
+    license = stdenv.lib.licenses.gpl3;
   };
 }

pkgs/development/misc/intelgen4asm/default.nix

@@ -15,7 +15,7 @@ stdenv.mkDerivation rec {
 
   meta = {
     homepage = http://cgit.freedesktop.org/xorg/app/intel-gen4asm/;
-    license = "MIT";
+    license = stdenv.lib.licenses.mit;
     description = "Program to compile an assembly language for the Intel 965 Express Chipset";
   };
 }