msvc: tests/t0403-lists.c: Fix a compiler warning

For more recent versions of msvc, the time_t type, as returned by
the time() function, is a 64-bit type. The srand() function, however,
expects an 'unsigned int' input parameter, leading to the warning.

Signed-off-by: Ramsay Jones <ramsay@ramsay1.demon.co.uk>
Signed-off-by: Andreas Ericsson <ae@op5.se>

tests/t0403-lists.c

@@ -20,7 +20,7 @@ BEGIN_TEST(list_timesort_test)
     }
 
     memset(&list, 0x0, sizeof(git_commit_list));
-    srand(time(NULL));
+    srand((unsigned int)time(NULL));
 
     for (t = 0; t < 20; ++t)
     {