[turbofan] Use NumAllocatableRegisters() instead of kMaxNumAllocatableRegisters.

src/compiler/register-configuration.cc

Index: src/compiler/register-configuration.cc
diff --git a/src/compiler/register-configuration.cc b/src/compiler/register-configuration.cc
index a3d3be1790a6a41ea64fb506f3be4b81d525fd3a..ebe6cfe23c34f3942b3945bc8d6f57687cbccedd 100644
--- a/src/compiler/register-configuration.cc
+++ b/src/compiler/register-configuration.cc
@@ -25,7 +25,7 @@ class ArchDefaultRegisterConfiguration : public RegisterConfiguration {
                               1,
                               1,
 #else
-                              DoubleRegister::kMaxNumAllocatableRegisters,
+                              DoubleRegister::NumAllocatableRegisters(),
                               DoubleRegister::NumAllocatableAliasedRegisters(),
 #endif
                               general_register_name_table_,
@@ -35,7 +35,9 @@ class ArchDefaultRegisterConfiguration : public RegisterConfiguration {
     for (int i = 0; i < Register::kMaxNumAllocatableRegisters; ++i) {
       general_register_name_table_[i] = Register::AllocationIndexToString(i);
     }
-    for (int i = 0; i < DoubleRegister::kMaxNumAllocatableRegisters; ++i) {
+    DCHECK_GE(DoubleRegister::kMaxNumAllocatableRegisters,
+              DoubleRegister::NumAllocatableRegisters());
+    for (int i = 0; i < DoubleRegister::NumAllocatableRegisters(); ++i) {
       double_register_name_table_[i] =
           DoubleRegister::AllocationIndexToString(i);
     }