x86: merge iommu initialization parameters

we merge the iommu initialization parameters in pci-dma.c
Nice thing, that both architectures at least recognize the same
parameters.

usedac i386 parameter is marked for deprecation

Signed-off-by: Glauber Costa <gcosta@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/Documentation/feature-removal-schedule.txt b/Documentation/feature-removal-schedule.txt
index af0e939..309c47b 100644
--- a/Documentation/feature-removal-schedule.txt
+++ b/Documentation/feature-removal-schedule.txt
@@ -282,6 +282,13 @@
 	out-of-tree driver.
 Who:	Thomas Gleixner <tglx@linutronix.de>
 
+----------------------------
+
+What:	usedac i386 kernel parameter
+When:	2.6.27
+Why:	replaced by allowdac and no dac combination
+Who:	Glauber Costa <gcosta@redhat.com>
+
 ---------------------------
 
 What:	/sys/o2cb symlink