Fix static initializers on x64

src/x64/assembler-x64.h

Index: src/x64/assembler-x64.h
diff --git a/src/x64/assembler-x64.h b/src/x64/assembler-x64.h
index 5bb1292f2fc6e294cc1b4eafbc610d0c84256fcf..aec50c911068e6624d06cb1567ba0a2ee875a512 100644
--- a/src/x64/assembler-x64.h
+++ b/src/x64/assembler-x64.h
@@ -202,16 +202,16 @@ const Register no_reg = { kRegister_no_reg_Code };
 
 #ifdef _WIN64
   // Windows calling convention
-  const Register arg_reg_1 = rcx;
-  const Register arg_reg_2 = rdx;
-  const Register arg_reg_3 = r8;
-  const Register arg_reg_4 = r9;
+  const Register arg_reg_1 = { kRegister_rcx_Code };
+  const Register arg_reg_2 = { kRegister_rdx_Code };
+  const Register arg_reg_3 = { kRegister_r8_Code };
+  const Register arg_reg_4 = { kRegister_r9_Code };
 #else
   // AMD64 calling convention
-  const Register arg_reg_1 = rdi;
-  const Register arg_reg_2 = rsi;
-  const Register arg_reg_3 = rdx;
-  const Register arg_reg_4 = rcx;
+  const Register arg_reg_1 = { kRegister_rdi_Code };
+  const Register arg_reg_2 = { kRegister_rsi_Code };
+  const Register arg_reg_3 = { kRegister_rdx_Code };
+  const Register arg_reg_4 = { kRegister_rcx_Code };
 #endif  // _WIN64
 
 struct XMMRegister {