Adjust loops to use size_t instead of int

Gbp-Dch: ignore

test/interactive-helper/createdeb-cve-2020-27350.cc

@@ -231,7 +231,7 @@ static void createtar(const int fd)
       struct TarHeader t;
       char buf[512];
    } t;
-   for (int i = 0; i < sizeof(t.buf); i++)
+   for (size_t i = 0; i < sizeof(t.buf); i++)
       t.buf[i] = '7';
    memcpy(t.t.Name, "unterminatedName", 16);
    memcpy(t.t.UserName, "userName", 8);
@@ -247,11 +247,11 @@ static void createtar(const int fd)
    memset(t.t.Checksum, ' ', sizeof(t.t.Checksum));
 
    unsigned long sum = 0;
-   for (int i = 0; i < sizeof(t.buf); i++)
+   for (size_t i = 0; i < sizeof(t.buf); i++)
       sum += t.buf[i];
 
    int written = sprintf(t.t.Checksum, "%lo", sum);
-   for (int i = written; i < sizeof(t.t.Checksum); i++)
+   for (size_t i = written; i < sizeof(t.t.Checksum); i++)
       t.t.Checksum[i] = ' ';
    write_chk(fd, t.buf, sizeof(t.buf));
 }