Remove blk_queue_io_opt() autotools check

This is needed for supporting kernels earlier than 2.6.30. Support for
those kernels was dropped, so we can safely remove this check.

Signed-off-by: Richard Yao <ryao@gentoo.org>
Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

config/kernel-blk-queue-io-opt.m4

@@ -1,24 +0,0 @@
-dnl #
-dnl # 2.6.30 API change
-dnl # The blk_queue_io_opt() function was added to indicate the optimal
-dnl # I/O size for the device.
-dnl #
-AC_DEFUN([ZFS_AC_KERNEL_BLK_QUEUE_IO_OPT], [
-	AC_MSG_CHECKING([whether blk_queue_io_opt() is available])
-	tmp_flags="$EXTRA_KCFLAGS"
-	EXTRA_KCFLAGS="${NO_UNUSED_BUT_SET_VARIABLE}"
-	ZFS_LINUX_TRY_COMPILE([
-		#include <linux/blkdev.h>
-	],[
-		struct request_queue *q = NULL;
-		unsigned int opt = 1;
-		(void) blk_queue_io_opt(q, opt);
-	],[
-		AC_MSG_RESULT(yes)
-		AC_DEFINE(HAVE_BLK_QUEUE_IO_OPT, 1,
-		          [blk_queue_io_opt() is available])
-	],[
-		AC_MSG_RESULT(no)
-	])
-	EXTRA_KCFLAGS="$tmp_flags"
-])

config/kernel.m4

@@ -29,7 +29,6 @@ AC_DEFUN([ZFS_AC_CONFIG_KERNEL], [
 	ZFS_AC_KERNEL_BLK_QUEUE_FLUSH
 	ZFS_AC_KERNEL_BLK_QUEUE_MAX_HW_SECTORS
 	ZFS_AC_KERNEL_BLK_QUEUE_MAX_SEGMENTS
-	ZFS_AC_KERNEL_BLK_QUEUE_IO_OPT
 	ZFS_AC_KERNEL_BLK_QUEUE_NONROT
 	ZFS_AC_KERNEL_BLK_QUEUE_DISCARD
 	ZFS_AC_KERNEL_BLK_FETCH_REQUEST