dmar, x86: Use function stubs when CONFIG_INTR_REMAP is disabled

The stubs for CONFIG_INTR_REMAP disabled need to be functions
instead of values to eliminate build warnings.

 arch/x86/kernel/apic/apic.c: In function 'lapic_suspend':
 arch/x86/kernel/apic/apic.c:2060:3: warning: statement with no effect
 arch/x86/kernel/apic/apic.c: In function 'lapic_resume':
 arch/x86/kernel/apic/apic.c:2137:3: warning: statement with no effect

Reported-and-Tested-by: Fabio Comolli <fabio.comolli@gmail.com>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Jesse Barnes <jbarnes@virtuousgeek.org>
LKML-Reference: <20101122124834.74429004.randy.dunlap@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

include/linux/dmar.h

@@ -175,10 +175,21 @@ static inline int set_msi_sid(struct irte *irte, struct pci_dev *dev)
 	return 0;
 }
 
-#define enable_intr_remapping(mode)	(-1)
-#define disable_intr_remapping()	(0)
-#define reenable_intr_remapping(mode)	(0)
 #define intr_remapping_enabled		(0)
+
+static inline int enable_intr_remapping(int eim)
+{
+	return -1;
+}
+
+static inline void disable_intr_remapping(void)
+{
+}
+
+static inline int reenable_intr_remapping(int eim)
+{
+	return 0;
+}
 #endif
 
 /* Can't use the common MSI interrupt functions