RISC-V: Request newstat syscalls

Since commit 82b355d1 ("y2038: Remove newstat family from default
syscall set"), riscv images fail to boot with the following error.

/sbin/init: error while loading shared libraries: libc.so.6:
	cannot stat shared object: Error 38
Kernel panic - not syncing: Attempted to kill init! exitcode=0x00007f00

Explicitly request newstat syscalls to fix the problem.

Fixes: 82b355d1 ("y2038: Remove newstat family from default syscall set")
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>