[turbofan] Rename floating point register / slot methods.

test/cctest/compiler/test-gap-resolver.cc

Index: test/cctest/compiler/test-gap-resolver.cc
diff --git a/test/cctest/compiler/test-gap-resolver.cc b/test/cctest/compiler/test-gap-resolver.cc
index 7f85088809403a73c79461c50290bfebd49f5d86..9781aeb5cdb41de4c82303f0f6fc5d48c878af91 100644
--- a/test/cctest/compiler/test-gap-resolver.cc
+++ b/test/cctest/compiler/test-gap-resolver.cc
@@ -81,7 +81,7 @@ class InterpreterState {
     if (!is_constant) {
       if (op.IsRegister()) {
         index = LocationOperand::cast(op).GetRegister().code();
-      } else if (op.IsDoubleRegister()) {
+      } else if (op.IsFPRegister()) {
         index = LocationOperand::cast(op).GetDoubleRegister().code();
       } else {
         index = LocationOperand::cast(op).index();