drm/nouveau/fifo: Remove duplicated include in chan.c

./drivers/gpu/drm/nouveau/nvkm/engine/fifo/chan.c: chid.h is included more than once.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Closes: https://bugzilla.openanolis.cn/show_bug.cgi?id=7603


Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Reviewed-by: Lyude Paul <lyude@redhat.com>
Signed-off-by: Lyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20231122004926.84933-1-yang.lee@linux.alibaba.com