Recent nandfs commits broke buildworld with clang

[Vladimir Sharun]

env MACHINE=amd64 CPP="/usr/bin/clang-cpp"  sh /usr/src/usr.bin/kdump/mkioctls print /usr/obj/usr/src/tmp/usr/include > ioctl.c
<stdin>:34:10: fatal error: 'fs/nandfs/nandfs_fs.h' file not found
#include <fs/nandfs/nandfs_fs.h>
         ^
1 error generated.
/bin/sh /usr/src/usr.bin/kdump/../../sys/kern/makesyscalls.sh  /usr/src/usr.bin/kdump/../../sys/amd64/linux32/syscalls.master /usr/src/usr.bin/kdump/linux_syscalls.conf
echo "int nlinux_syscalls = sizeof(linux_syscallnames) / sizeof(linux_syscallnames[0]);"  >> linux_syscalls.c
rm -f .depend
CC='/usr/bin/clang' mkdep -f .depend -a    -I/usr/src/usr.bin/kdump/../ktrace -I/usr/src/usr.bin/kdump -I/usr/src/usr.bin/kdump/../.. -I. -std=gnu99  kdump_subr.c /usr/src/usr.bin/kdump/kdump.c ioctl.c /usr/src/usr.bin/kdump/../ktrace/subr.c linux_syscalls.c
ioctl.c:57:10: fatal error: 'fs/nandfs/nandfs_fs.h' file not found
#include <fs/nandfs/nandfs_fs.h>
         ^
1 error generated.
mkdep: compile failed
*** [.depend] Error code 1

r235624 on amd64

# clang -v
FreeBSD clang version 3.1 (branches/release_31 155985) 20120503
Target: x86_64-unknown-freebsd10.0
Thread model: posix

Didn't test it with stock gcc.