irq_domain/x86: Convert x86 (embedded) to use common irq_domain

This patch removes the x86-specific definition of irq_domain and replaces
it with the common implementation.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 5bed94e1..e0829a6 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -398,6 +398,7 @@
 	select X86_REBOOTFIXUPS
 	select OF
 	select OF_EARLY_FLATTREE
+	select IRQ_DOMAIN
 	---help---
 	  Select for the Intel CE media processor (CE4100) SOC.
 	  This option compiles in support for the CE4100 SOC for settop
@@ -2076,6 +2077,7 @@
 	select GPIOLIB
 	select OF
 	select OF_PROMTREE
+	select IRQ_DOMAIN
 	---help---
 	  Add support for detecting the unique features of the OLPC
 	  XO hardware.