fix(cbor): Fix build with picolibc (IEC-512)

[abobija]

Checklist

• Component contains License
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Change description

Build of project that uses espressif/cbor^0.6.1~4 component and picolibc (with idf v6+) fails since picolibc does not have implementation of fopencookie function and cookie_io_functions_t typedef.

By defining __APPLE__ we are switching to picolibc supported funopen alternative that makes project successfully compiled on idf v6+ using picolibc. Note that CONFIG_LIBC_PICOLIBC_NEWLIB_COMPATIBILITY still needs to be enabled to compile with picolibc, even if we switch to __APPLE__.

It would be nice if cbor component could work without defining CONFIG_LIBC_PICOLIBC_NEWLIB_COMPATIBILITY and rely completely on picolibc without any hacks.

I've opened a PR in origin tinycbor's repo as well to support picolibc, so maybe we will accomplish something:
intel/tinycbor#319

Maybe to wait if intel's tinycbor is going to support picolibc...

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[mahavirj]

@Lapshin PTAL

[Lapshin]

@abobija , thanks for the PR.

Note that CONFIG_LIBC_PICOLIBC_NEWLIB_COMPATIBILITY still needs to be enabled to compile with picolibc, even if we switch to APPLE.

Could you please elaborate on why it still needs to be enabled?
Regardless of whether this is required, I don't consider this change valuable. Rather than defining __APPLE__, __linux__, __windows__, and other unrelated macros (ESP32 does not fall under any of these), the original https://github.com/intel/tinycbor sources should detect the availability of libc functions in their configure script (or whatever mechanism they use for this purpose).

[Lapshin]

@abobija , I thought that commit espressif/esp-idf@51f1861 exists for v6.0, but for some reason is present only in master branch. Will make a backport

[Lapshin]

espressif/esp-idf@ae8d484 in release/v6.0 branch. It just did not add in time for v6.0 release. Should be released with bugfix version v6.0.1