include/asm-powerpc/nvram.h needs list.h

CC [M]  sound/ppc/awacs.o
In file included from sound/ppc/awacs.c:24:
include/asm/nvram.h:62: error: field 'partition' has incomplete type

Reported-by: Mariusz Kozlowski <m.kozlowski@tuxland.pl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>