ALSA: HDA: Use LPIB Position fix for Intel SCH Poulsbo

Several people with this chipset have reported inconsistent/sloppy
values for position reporting when the DMA position buffer is used,
and that setting position_fix=1 have fixed their problems.

BugLink: https://bugs.launchpad.net/bugs/825709
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

sound/pci/hda/hda_intel.c

@@ -2971,7 +2971,8 @@ static DEFINE_PCI_DEVICE_TABLE(azx_ids) = {
 	/* SCH */
 	{ PCI_DEVICE(0x8086, 0x811b),
 	  .driver_data = AZX_DRIVER_SCH | AZX_DCAPS_SCH_SNOOP |
-	  AZX_DCAPS_BUFSIZE},
+	  AZX_DCAPS_BUFSIZE | AZX_DCAPS_POSFIX_LPIB }, /* Poulsbo */
+	/* ICH */
 	{ PCI_DEVICE(0x8086, 0x2668),
 	  .driver_data = AZX_DRIVER_ICH | AZX_DCAPS_OLD_SSYNC |
 	  AZX_DCAPS_BUFSIZE },  /* ICH6 */