powerpc: Remove useless config comment in asm/percpu.h

commit 0db880f ("powerpc: Avoid nmi_enter/nmi_exit in real mode
interrupt.") has a config comment typo, and the #if/#else/#endif section
is small and doesn't nest additional #ifdefs so the comment is useless
and should be removed completely.

Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20240807025604.2817577-1-ruanjinjie@huawei.com

arch/powerpc/include/asm/percpu.h

@@ -23,7 +23,7 @@ DECLARE_STATIC_KEY_FALSE(__percpu_first_chunk_is_paged);
 		(static_key_enabled(&__percpu_first_chunk_is_paged.key))
 #else
 #define percpu_first_chunk_is_paged	false
-#endif /* CONFIG_PPC64 && CONFIG_SMP */
+#endif
 
 #include <asm-generic/percpu.h>