[PATCH RFT v3] scripts: define _GNU_SOURCE for all source files

[Jules Maselbas]

Tested on alpine linux with musl 1.2.5, and it compiled without issue

On Mon Jan 27, 2025 at 8:51 PM CET, Ahmad Fatoum wrote:
> musl doesn't define loff_t, unless _GNU_SOURCE is defined, which
> we don't do everywhere and glibc didn't mind.
>
> This led to build errors with musl when code makes it into
> scripts/ that uses loff_t. This was already fixed once e.g. in commit
> c0d065fb0aa0 ("scripts: bareboximd: remove usage of loff_t").
>
> To fix this issue for good, let's define _GNU_SOURCE globally for all files.
>
> Link: https://lore.kernel.org/all/CAMKF1sqX7gFCEH78fHS+jkUSieL5crAU_RwAUO-daJL0u+fj0g@mail.gmail.com/
> Fixes: 5171f4d0696f ("scripts: implement read_fd and pread_full for tools")
> Suggested-by: Khem Raj <raj.khem at gmail.com>
> Reported-by: Enrico Jörns <ejo at pengutronix.de>
> Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
> ---
> @Enrico, please give this a test. I only tested against glibc.
>
> v2 -> v3:
>   - set _GNU_SOURCE instead of defining loff_t (Khem)
> v1 -> v2:
>   - include <linux/types.h> from scripts/common.h (Enrico)
> v2 was here:
>   https://lore.barebox.org/barebox/20250127143146.2965544-1-a.fatoum@pengutronix.de/T/#u
> ---