iommu/amd: Remove AMD_IOMMU_STATS

Commit e85e8f69cedb ("iommu/amd: Remove statistics code")
removed that configuration.

Also remove function definition (suggested by Joerg Roedel)

Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

arch/x86/configs/x86_64_defconfig

@@ -255,7 +255,6 @@ CONFIG_RTC_CLASS=y
 CONFIG_DMADEVICES=y
 CONFIG_EEEPC_LAPTOP=y
 CONFIG_AMD_IOMMU=y
-CONFIG_AMD_IOMMU_STATS=y
 CONFIG_INTEL_IOMMU=y
 # CONFIG_INTEL_IOMMU_DEFAULT_ON is not set
 CONFIG_EFI_VARS=y

drivers/iommu/amd_iommu_proto.h

@@ -78,12 +78,6 @@ static inline int amd_iommu_create_irq_domain(struct amd_iommu *iommu)
 extern int amd_iommu_complete_ppr(struct pci_dev *pdev, int pasid,
 				  int status, int tag);
 
-#ifndef CONFIG_AMD_IOMMU_STATS
-
-static inline void amd_iommu_stats_init(void) { }
-
-#endif /* !CONFIG_AMD_IOMMU_STATS */
-
 static inline bool is_rd890_iommu(struct pci_dev *pdev)
 {
 	return (pdev->vendor == PCI_VENDOR_ID_ATI) &&