iommu/amd: fix SEV-TIO support reporting

Commit eeb934137deb ("iommu/amd: Report SEV-TIO support") was confused
about the config options that expose amd_iommu_sev_tio_supported(), and
made the declaration (and alternative dummy function) conditional on the
CONFIG_AMD_IOMMU config option.

But the code is actually dependent on CONFIG_KVM_AMD_SEV, resulting in

ERROR: modpost: "amd_iommu_sev_tio_supported" [drivers/crypto/ccp/ccp.ko] undefined!
make[2]: *** [scripts/Makefile.modpost:147: Module.symvers] Error 1

if you have the AMD iommu enabled, but don't enable KVM_AMD_SEV support.

Fix it by moving the declaration into the right #ifdef section in the
header file.

Fixes: eeb934137deb ("iommu/amd: Report SEV-TIO support")
Cc: Alexey Kardashevskiy <[e-mail]>
Cc: Joerg Roedel <[e-mail]>
Cc: Vasant Hegde <[e-mail]>
Cc: Tom Lendacky <[e-mail]>
Cc: Dan Williams <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

include/linux/amd-iommu.h

···
 struct pci_dev;
 
 extern void amd_iommu_detect(void);
-extern bool amd_iommu_sev_tio_supported(void);
 
 #else /* CONFIG_AMD_IOMMU */
 
 static inline void amd_iommu_detect(void) { }
-static inline bool amd_iommu_sev_tio_supported(void) { return false; }
 
 #endif /* CONFIG_AMD_IOMMU */
 
···
 
 #ifdef CONFIG_KVM_AMD_SEV
 int amd_iommu_snp_disable(void);
+extern bool amd_iommu_sev_tio_supported(void);
 #else
 static inline int amd_iommu_snp_disable(void) { return 0; }
+static inline bool amd_iommu_sev_tio_supported(void) { return false; }
 #endif
 
 #endif /* _ASM_X86_AMD_IOMMU_H */