selftests/kcmp: Make the test output consistent and clear

Make the output format of this test consistent. Currently the output is
as follows:

+TAP version 13
+1..1
+# selftests: kcmp: kcmp_test
+# pid1: 45814 pid2: 45815 FD: 1 FILES: 1 VM: 2 FS: 1 SIGHAND: 2
+ IO: 0 SYSVSEM: 0 INV: -1
+# PASS: 0 returned as expected
+# PASS: 0 returned as expected
+# PASS: 0 returned as expected
+# # Planned tests != run tests (0 != 3)
+# # Totals: pass:3 fail:0 xfail:0 xpass:0 skip:0 error:0
+# # Planned tests != run tests (0 != 3)
+# # Totals: pass:3 fail:0 xfail:0 xpass:0 skip:0 error:0
+# # Totals: pass:0 fail:0 xfail:0 xpass:0 skip:0 error:0
+ok 1 selftests: kcmp: kcmp_test

With this patch applied the output is as follows:

+TAP version 13
+1..1
+# selftests: kcmp: kcmp_test
+# TAP version 13
+# 1..3
+# pid1: 46330 pid2: 46331 FD: 1 FILES: 2 VM: 2 FS: 2 SIGHAND: 1
+ IO: 0 SYSVSEM: 0 INV: -1
+# PASS: 0 returned as expected
+# PASS: 0 returned as expected
+# PASS: 0 returned as expected
+# # Totals: pass:3 fail:0 xfail:0 xpass:0 skip:0 error:0
+ok 1 selftests: kcmp: kcmp_test

Signed-off-by: Gautam Menghani <[e-mail]>
Signed-off-by: Shuah Khan <[e-mail]>

tools/testing/selftests/kcmp/kcmp_test.c

···
 		int pid2 = getpid();
 		int ret;
 
+		ksft_print_header();
+		ksft_set_plan(3);
+
 		fd2 = open(kpath, O_RDWR, 0644);
 		if (fd2 < 0) {
 			perror("Can't open file");
···
 			ksft_inc_pass_cnt();
 		}
 
-		ksft_print_cnts();
 
 		if (ret)
 			ksft_exit_fail();
···
 
 	waitpid(pid2, &status, P_ALL);
 
-	return ksft_exit_pass();
+	return 0;
 }