fix all positioned uses as helper (not included anymore)

lib/arm/instructions/call_instruction.rb

@@ -48,7 +48,7 @@ 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 =  @first.position - self.position - 8
+        arg =  Positioned.position(@first) - Positioned.position(self) - 8
       when Parfait::TypedMethod
         # But, for methods, this happens to be the size of the object header,
         # so there it balances out, but not blocks

lib/arm/instructions/logic_instruction.rb

@@ -91,7 +91,7 @@ module Arm
         (@left.is_a?(Symbol) and !Register::RegisterValue.look_like_reg(@left)))
         # do pc relative addressing with the difference to the instuction
         # 8 is for the funny pipeline adjustment (ie pointing to fetch and not execute)
-        right = @left.position - self.position - 8
+        right = Positioned.position(@left) - Positioned.position(self) - 8
         if( (right < 0) && ((opcode == :add) || (opcode == :sub)) )
           right *= -1   # this works as we never issue sub only add
           set_opcode :sub  # so (as we can't change the sign permanently) we can change the opcode