[Skiboot] [PATCH] fix: Fix compile errors with GCC 15

[Reza Arbab]

On Fri, Mar 28, 2025 at 11:13:10PM +0530, Aditya Gupta wrote:
>Based on gcc source code, nonstring attribute has been there since
>gcc 8. I have tested the attribute till GCC 8.5, it treats nonstring
>as a known attribute (and ignores any unknown attributes).
>
>https://github.com/gcc-mirror/gcc/blob/58b59251ea22913ce0d5871db64f5d24f2b15493/include/ansidecl.h#L245
>
>But the error 'null-terminated-strings' seems to be recently introduced
>in gcc 15 only, introduced with this patch:
>https://gcc.gnu.org/pipermail/gcc-patches/2024-June/656014.html

When we first hit this error, I started ignoring it via commit 
009fd0976006 ("hdata/test: Build with 
-Wno-error=unterminated-string-initialization").

Using the nonstring attribute is a better fix, so I've reverted that 
patch and applied yours. Thanks!

-- 
Reza Arbab