selftests: kvm: Fix -Wformat warnings

Fixes the following warnings:

dirty_log_test.c: In function ‘help’:
dirty_log_test.c:216:9: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 2 has type ‘int’ [-Wformat=]
printf(" -i: specify iteration counts (default: %"PRIu64")\n",
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from include/test_util.h:18:0,
from dirty_log_test.c:16:
/usr/include/inttypes.h:105:34: note: format string is defined here
# define PRIu64 __PRI64_PREFIX "u"
dirty_log_test.c:218:9: warning: format ‘%lu’ expects argument of type ‘long unsigned int’, but argument 2 has type ‘int’ [-Wformat=]
printf(" -I: specify interval in ms (default: %"PRIu64" ms)\n",
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from include/test_util.h:18:0,
from dirty_log_test.c:16:
/usr/include/inttypes.h:105:34: note: format string is defined here
# define PRIu64 __PRI64_PREFIX "u"

Signed-off-by: Andrea Parri <[e-mail]>
Signed-off-by: Shuah Khan (Samsung OSG) <[e-mail]>

tools/testing/selftests/kvm/dirty_log_test.c

···
 /* How many pages to dirty for each guest loop */
 #define  TEST_PAGES_PER_LOOP            1024
 /* How many host loops to run (one KVM_GET_DIRTY_LOG for each loop) */
-#define  TEST_HOST_LOOP_N               32
+#define  TEST_HOST_LOOP_N               32UL
 /* Interval for each host loop (ms) */
-#define  TEST_HOST_LOOP_INTERVAL        10
+#define  TEST_HOST_LOOP_INTERVAL        10UL
 
 /*
  * Guest variables.  We use these variables to share data between host