Use default libc with mosquitto/asio ports (IDFGH-16962)

[david-cermak]

Answers checklist.

• I have read the documentation for esp-protocols components and the issue is not addressed there.
• I have updated my esp-protocols branch (master or release) to the latest version and checked that the issue is present there.
• I have searched the issue tracker for a similar issue and not found a similar issue.

What component are you using? If you choose Other, provide details in More Information.

Other

component version

No response

IDF version.

v6.0

More Information.

Due to some initial issues with picolib in IDFv6.x, we had to apply a few workarounds:

• fix(mosq): Fix build with the new picolibc #973
• [asio]: Fix picolib missing pthread_sigmask() declaration #974