dma-buf: Include ioctl.h in UAPI header

include/uapi/linux/dma-buf.h uses several macros from ioctl.h to define
its ioctl commands. However, it does not include ioctl.h itself. So,
if userspace source code tries to include the dma-buf.h file without
including ioctl.h, it can result in build failures.

Therefore, include ioctl.h in the dma-buf UAPI header.

Signed-off-by: Isaac J. Manjarres <isaacmanjarres@google.com>
Reviewed-by: T.J. Mercier <tjmercier@google.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/20260303002309.1401849-1-isaacmanjarres@google.com