include/qemu: remove return after g_assert_not_reached()

This patch is part of a series that moves towards a consistent use of
g_assert_not_reached() rather than an ad hoc mix of different
assertion mechanisms.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org>
Message-ID: <20240919044641.386068-26-pierrick.bouvier@linaro.org>
Signed-off-by: Thomas Huth <thuth@redhat.com>

include/qemu/pmem.h

@@ -22,7 +22,6 @@ pmem_memcpy_persist(void *pmemdest, const void *src, size_t len)
     /* If 'pmem' option is 'on', we should always have libpmem support,
        or qemu will report a error and exit, never come here. */
     g_assert_not_reached();
-    return NULL;
 }
 
 static inline void