8324184: Windows VS2010 build failed with "error C2275: 'int64_t'"

Reviewed-by: serb
Backport-of: 4f80edfae10e83f2709f297a553d2128712e4b51

src/java.base/share/native/libverify/check_code.c

@@ -1693,12 +1693,13 @@ static int instruction_length(unsigned char *iptr, unsigned char *end)
     switch (instruction) {
         case JVM_OPC_tableswitch: {
             int *lpc = (int *)UCALIGN(iptr + 1);
+            int64_t low, high, index;
             if (lpc + 2 >= (int *)end) {
                 return -1; /* do not read pass the end */
             }
-            int64_t low  = _ck_ntohl(lpc[1]);
-            int64_t high = _ck_ntohl(lpc[2]);
-            int64_t index = high - low;
+            low  = _ck_ntohl(lpc[1]);
+            high = _ck_ntohl(lpc[2]);
+            index = high - low;
             // The value of low must be less than or equal to high - i.e. index >= 0
             if ((index < 0) || (index > 65535)) {
                 return -1;      /* illegal */