selftests/exec: binfmt_script: Add the overall result line according to TAP

The following line is missing from the test's execution. Add it to make
it fully TAP conformant:
  # Totals: pass:27 fail:0 xfail:0 xpass:0 skip:0 error:0

Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20240304155928.1818928-1-usama.anjum@collabora.com
Signed-off-by: Kees Cook <keescook@chromium.org>

Author: Muhammad Usama Anjum

tools/testing/selftests/exec/binfmt_script.py

@@ -16,6 +16,8 @@
 NAME_MAX=int(subprocess.check_output(["getconf", "NAME_MAX", "."]))
 
 test_num=0
+pass_num=0
+fail_num=0
 
 code='''#!/usr/bin/perl
 print "Executed interpreter! Args:\n";
@@ -42,7 +44,7 @@
 # ...
 def test(name, size, good=True, leading="", root="./", target="/perl",
                      fill="A", arg="", newline="\n", hashbang="#!"):
-    global test_num, tests, NAME_MAX
+    global test_num, pass_num, fail_num, tests, NAME_MAX
     test_num += 1
     if test_num > tests:
         raise ValueError("more binfmt_script tests than expected! (want %d, expected %d)"
@@ -80,16 +82,20 @@ def test(name, size, good=True, leading="", root="./", target="/perl",
         if good:
             print("ok %d - binfmt_script %s (successful good exec)"
                   % (test_num, name))
+            pass_num += 1
         else:
             print("not ok %d - binfmt_script %s succeeded when it should have failed"
                   % (test_num, name))
+            fail_num = 1
     else:
         if good:
             print("not ok %d - binfmt_script %s failed when it should have succeeded (rc:%d)"
                   % (test_num, name, proc.returncode))
+            fail_num = 1
         else:
             print("ok %d - binfmt_script %s (correctly failed bad exec)"
                   % (test_num, name))
+            pass_num += 1
 
     # Clean up crazy binaries
     os.unlink(script)
@@ -166,6 +172,8 @@ def test(name, size, good=True, leading="", root="./", target="/perl",
 test(name="two-under-leading",   size=int(SIZE/2), leading=" ")
 test(name="two-under-lead-trunc-arg", size=int(SIZE/2), leading=" ", arg=" ")
 
+print("# Totals: pass:%d fail:%d xfail:0 xpass:0 skip:0 error:0" % (pass_num, fail_num))
+
 if test_num != tests:
     raise ValueError("fewer binfmt_script tests than expected! (ran %d, expected %d"
                      % (test_num, tests))