Follow o_cloexe semantics when calling the exec function

[Donny9]

Summary

sched/task: close file descriptor with O_CLOEXEC before active task or exec

modify:

1. Ensure that the child task copies all fds of the parent task,
   including those with O_CLOEXE.
2. Make sure spawn_file_action is executed under fd with O_CLOEXEC,
   otherwise it will fail.
3. When a new task is activated or exec is called, close all fds
   with O_CLOEXEC flags.

fs/dup3: impletement dup3/nx_dup3_from_tcb function

 refs: https://man7.org/linux/man-pages/man2/dup.2.html

fs/dup/dup2: don't add O_CLOEXEC for new file descriptor

refs: https://man7.org/linux/man-pages/man2/dup.2.html

The two file descriptors do not share file descriptor flags (the
close-on-exec flag).  The close-on-exec flag (FD_CLOEXEC; see
fcntl(2)) for the duplicate descriptor is off.

libs/lib_psfa_adddup2.c: remove workaround aboud dup2

Because popen no longer needs to rely on intermediate
tasks to start command tasks.

Impact

posix_spawn/exec_module/task_create/... with exec or start new task

Testing

Vela

[acassis]

@Donny9 I think it should be a nice idea to include a popen test to apps/testing/ostest. Testing only on Vela will be like "It works on my machine" TM! :-D

[xiaoxiang781216]

@Donny9 I think it should be a nice idea to include a popen test to apps/testing/ostest. Testing only on Vela will be like "It works on my machine" TM! :-D

apache/nuttx-apps#2163 contain the related change to make popen more conform the standard

[acassis]

@Donny9 I think it should be a nice idea to include a popen test to apps/testing/ostest. Testing only on Vela will be like "It works on my machine" TM! :-D

apache/nuttx-apps#2163 contain the related change to make popen more conform the standard

@xiaoxiang781216 actually it only created the popen() function. I'm talking about adding a popen() test into ostest

[Donny9]

@Donny9 I think it should be a nice idea to include a popen test to apps/testing/ostest. Testing only on Vela will be like "It works on my machine" TM! :-D

apache/nuttx-apps#2163 contain the related change to make popen more conform the standard

@xiaoxiang781216 actually it only created the popen() function. I'm talking about adding a popen() test into ostest

@acassis OK, I will add popen test to ostest in another PR soon~, so we can merge this pr first, thanks~

[xiaoxiang781216]

@Donny9 please rebase the patch

[Donny9]

@Donny9 please rebase the patch

Done~