rename Position get/set

lib/arm/instructions/call_instruction.rb

@@ -47,12 +47,12 @@ module Arm
         # relative addressing for jumps/calls
         # but because of the arm "theoretical" 3- stage pipeline,
         # we have to subtract 2 words (fetch/decode)
-        arg =  Risc::Position.position(@first) - Risc::Position.position(self) - 8
+        arg =  Risc::Position.get(@first) - Risc::Position.get(self) - 8
       when Parfait::BinaryCode
         # But, for methods, this happens to be the size of the object header,
         # so there it balances out, but not blocks
         # have to use the code, not the method object for methods
-        arg = Risc::Position.position(@first) - Risc::Position.position(self) + 4
+        arg = Risc::Position.get(@first) - Risc::Position.get(self) + 4
       else
         arg = @first
       end