NVMe: Split header file into user-visible and kernel-visible pieces

To build user programs that call the NVMe ioctls, we need to have a
user header file.  Catch up to the new way of doing that by splitting
the header file into kernel and uapi portions.
Signed-off-by: Matthew Wilcox <matthew.r.wilcox@intel.com>

include/uapi/linux/Kbuild

@@ -281,6 +281,7 @@ header-y += nfs_mount.h
 header-y += nfsacl.h
 header-y += nl80211.h
 header-y += nubus.h
+header-y += nvme.h
 header-y += nvram.h
 header-y += omap3isp.h
 header-y += omapfb.h