This makes sure the heap posix_timer_slab provides objects aligned
compatible with the type timer_obj. It was previously set to align at 4
bytes. One example where this failed was on the SPARC which requires
access to int64_t to be 8-byte aligned.
In particular, struct timer_obj contains fields of type k_timer_t and
struct _timeout.
With this commit we now get the information on required alignment for
struct timer_obj from the compiler by using __alignof__().
Signed-off-by: Martin Åberg <martin.aberg@gaisler.com>
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