arm64: use linux/types.h in kvm.h

We should always use linux/types.h instead of asm/types.h for
consistency, and Kbuild actually warns about it:

./usr/include/asm/kvm.h:35: include of <linux/types.h> is preferred over <asm/types.h>

This patch does as Kbuild asks us.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>