x86 gart: rename symbols only used for the GART implementation

This patch renames the 4 symbols iommu_hole_init(), iommu_aperture,
iommu_aperture_allowed, iommu_aperture_disabled. All these symbols are only
used for the GART implementation of IOMMUs.

It adds and additional gart_ prefix to them.

Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/pci-dma_64.c b/arch/x86/kernel/pci-dma_64.c
index 66b3dc5..aa805b1 100644
--- a/arch/x86/kernel/pci-dma_64.c
+++ b/arch/x86/kernel/pci-dma_64.c
@@ -299,7 +299,7 @@
 	 * fall-back/fail-over reasons
 	 */
 #ifdef CONFIG_GART_IOMMU
-	iommu_hole_init();
+	gart_iommu_hole_init();
 #endif
 
 #ifdef CONFIG_CALGARY_IOMMU