Utilities: Fix -Wunreachable-code warnings from clang

Userland/Utilities/fgrep.cpp

@@ -25,5 +25,4 @@ int main(int argc, char** argv)
  return 0;
  VERIFY(str);
  }
- return 0;
 }

Userland/Utilities/ping.cpp

@@ -225,6 +225,4 @@ int main(int argc, char** argv)
 
  sleep(1);
  }
-
- return 0;
 }

Userland/Utilities/strace.cpp

@@ -790,6 +790,4 @@ int main(int argc, char** argv)
  return 1;
  }
  }
-
- return 0;
 }

Userland/Utilities/top.cpp

@@ -297,5 +297,4 @@ int main(int argc, char** argv)
  prev = move(current);
  sleep(top_option.delay_time);
  }
- return 0;
 }

Userland/Utilities/tt.cpp

@@ -58,7 +58,6 @@ int main(int argc, char** argv)
  &thread_id, nullptr, [](void*) -> void* {
  outln("Hi there, from the second thread!");
  pthread_exit((void*)0xDEADBEEF);
- return nullptr;
  },
  nullptr);
  if (rc < 0) {
@@ -96,8 +95,6 @@ int mutex_test()
  pthread_mutex_unlock(&mutex);
  sleep(1);
  }
- pthread_exit((void*)0xDEADBEEF);
- return nullptr;
  },
  nullptr);
  if (rc < 0) {
@@ -110,7 +107,6 @@ int mutex_test()
  pthread_mutex_unlock(&mutex);
  usleep(10000);
  }
- return 0;
 }
 
 int detached_test()
@@ -144,7 +140,6 @@ int detached_test()
  outln("I'm the secondary thread :^)");
  sleep(1);
  pthread_exit((void*)0xDEADBEEF);
- return nullptr;
  },
  nullptr);
  if (rc != 0) {
@@ -206,7 +201,6 @@ int priority_test()
  outln("I'm the secondary thread :^)");
  sleep(1);
  pthread_exit((void*)0xDEADBEEF);
- return nullptr;
  },
  nullptr);
  if (rc < 0) {
@@ -260,7 +254,6 @@ int stack_size_test()
  outln("I'm the secondary thread :^)");
  sleep(1);
  pthread_exit((void*)0xDEADBEEF);
- return nullptr;
  },
  nullptr);
  if (rc < 0) {
@@ -294,7 +287,6 @@ int staying_alive_test()
  sleep(3520);
  outln("Secondary thread exiting");
  pthread_exit((void*)0xDEADBEEF);
- return nullptr;
  },
  nullptr);
  if (rc < 0) {
@@ -354,7 +346,6 @@ int set_stack_test()
  outln("I'm the secondary thread :^)");
  sleep(1);
  pthread_exit((void*)0xDEADBEEF);
- return nullptr;
  },
  nullptr);
  if (rc < 0) {
@@ -386,7 +377,6 @@ int kill_test()
  sleep(100);
  outln("Secondary thread is still alive :^(");
  pthread_exit((void*)0xDEADBEEF);
- return nullptr;
  },
  nullptr);
  if (rc < 0) {

Userland/Utilities/yes.cpp

@@ -23,5 +23,4 @@ int main(int argc, char** argv)
 
  for (;;)
  puts(string);
- return 0;
 }