raw/ioat: fix build missing errno include

The inline functions in rte_idxd_rawdev_fns.h make use of rte_errno, but
the header with its definition is not included by that file leading to
build errors.

Fixes: f82c87eb14 ("raw/ioat: move idxd functions to separate file")
Cc: stable@dpdk.org

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

drivers/raw/ioat/rte_idxd_rawdev_fns.h

@@ -16,6 +16,7 @@
  */
 
 #include <stdint.h>
+#include <rte_errno.h>
 
 /*
  * Defines used in the data path for interacting with IDXD hardware.