Fix RHEL 7.4 bio_set_op_attrs build error

On RHEL 7.4, include/linux/bio.h now includes a macro for
bio_set_op_attrs that conflicts with the ifndef in ZFS
include/linux/blkdev_compat.h.  This patch fixes the build.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: George Melikov <mail@gmelikov.ru>
Reviewed-by: Giuseppe Di Natale <dinatale2@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #6234 
Closes #6271

config/kernel-bio-op.m4

@@ -69,7 +69,7 @@ AC_DEFUN([ZFS_AC_KERNEL_BIO_BI_OPF], [
 AC_DEFUN([ZFS_AC_KERNEL_HAVE_BIO_SET_OP_ATTRS], [
 	AC_MSG_CHECKING([whether bio_set_op_attrs is available])
 	ZFS_LINUX_TRY_COMPILE([
-		#include <linux/blk_types.h>
+		#include <linux/bio.h>
 	],[
 		struct bio *bio __attribute__ ((unused)) = NULL;