lib/system: Remove float from androideabi

There are two different official variations which differ in their float
support, so such a blanket statement is invalid.
`lib.systems.platforms.*android` already handles each case correctly.

Correcting an error in 827ef09140.

lib/systems/parse.nix

@@ -199,7 +199,7 @@ rec {
     msvc         = {};
     eabi         = {};
 
-    androideabi  = { float = "hard"; };
+    androideabi  = {};
     android      = {
       assertions = [
         { assertion = platform: !platform.isAarch32;