[8u] DWORD64 required for later Windows compilers

To compile with later Windows compilers, e.g. VS2017, DWORD is an error here:

src/os/windows/vm/os_windows.cpp

@@ -2261,9 +2296,9 @@
   assert((pc[1] & ~0x7) == 0xF8, "cannot handle non-register operands");
   assert(ctx->Rax == min_jint, "unexpected idiv exception");
   // set correct result values and continue after idiv instruction
- ctx->Rip = (DWORD)pc + 2; // idiv reg, reg is 2 bytes
- ctx->Rax = (DWORD)min_jint; // result
- ctx->Rdx = (DWORD)0; // remainder
+ ctx->Rip = (DWORD64)pc + 2; // idiv reg, reg is 2 bytes
+ ctx->Rax = (DWORD64)min_jint; // result
+ ctx->Rdx = (DWORD64)0; // remainder
   // Continue the execution
   #else
   PCONTEXT ctx = exceptionInfo->ContextRecord;


In JDK9, these DWORD changed to DWORD64 as a minor byproduct of:
8136421: JEP 243: Java-Level JVM Compiler Interface
...which we aren't implementing in jdk8 right now.