posix: signal SIGPIPE where necessary

[lukileczo]

Description

Send SIGPIPE where POSIX requires it. Changes do not affect AF_INET sockets, as LwIP does not return EPIPE.

Motivation and Context

Fixes phoenix-rtos/phoenix-rtos-project#733

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

How Has This Been Tested?

• Already covered by automatic testing.
• New test added: (add PR link here).
• Tested by hand on: ia32-generic-qemu

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing linter checks and tests passed.
• My changes generate no new compilation warnings for any of the targets.

Special treatment

• This PR needs additional PRs to work (list the PRs, preferably in merge-order).
• I will merge this PR by myself when appropriate.

[lukileczo]

I guess this has to wait for phoenix-rtos/phoenix-rtos-tests#310

[github-actions]

Unit Test Results

6 216 tests   - 194   5 601 ✅  - 178   33m 34s ⏱️ -8s
  354 suites ±  0     610 💤  -  20 
    1 files   ±  0       5 ❌ +  4 

For more details on these failures, see this check.

Results for commit ab27fad. ± Comparison against base commit 2e0c88c.

This pull request removes 199 and adds 5 tests. Note that renamed tests count towards both.

phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit.stdlib_exit.atexit_few_calls
phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit.stdlib_exit.atexit_register_inside
phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit.stdlib_exit.atexit_two_nodes
phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit.stdlib_exit.stream_flush
phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit.unistd_Exit.SIGCHLD_sent
phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit.unistd_Exit.chk_if_exits
phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit.unistd_Exit.close_streams
phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit.unistd_Exit.exit_status_waitpid
phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit.unistd_Exit.new_parent_id
phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit.unistd_Exit.no_atexit
…

phoenix-rtos-tests/libc/exit ‑ armv7a7-imx6ull-evk:phoenix-rtos-tests/libc/exit
phoenix-rtos-tests/libc/exit ‑ armv7a9-zynq7000-qemu:phoenix-rtos-tests/libc/exit
phoenix-rtos-tests/libc/exit ‑ armv7a9-zynq7000-zedboard:phoenix-rtos-tests/libc/exit
phoenix-rtos-tests/libc/exit ‑ ia32-generic-qemu:phoenix-rtos-tests/libc/exit
phoenix-rtos-tests/libc/misc ‑ armv7m4-stm32l4x6-nucleo:phoenix-rtos-tests/libc/misc