OvmfPkg/IoMmuDxe: clean up used library classes

The following library classes are not used by this module, so remove them
from the INF file's [LibraryClasses] section:
- DxeServicesTableLib
- UefiLib

The following library classes are used by this module, so add them to the
INF file's [LibraryClasses] section:
- BaseMemoryLib (e.g. via CopyMem())
- MemoryAllocationLib (e.g. via AllocatePool())

Sort the list of library classes (in both "IoMmuDxe.inf" and
"AmdSevIoMmu.h").

Remove all non-local #include directives from "IoMmuDxe.c"; both C files
of this module include "AmdSevIoMmu.h", and "AmdSevIoMmu.h" includes all
non-local headers already.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Brijesh Singh <brijesh.singh@amd.com>

OvmfPkg/IoMmuDxe/AmdSevIoMmu.h

@@ -24,11 +24,11 @@
 #include <Protocol/IoMmu.h>
 
 #include <Library/BaseLib.h>
-#include <Library/DebugLib.h>
 #include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/MemEncryptSevLib.h>
 #include <Library/MemoryAllocationLib.h>
 #include <Library/UefiBootServicesTableLib.h>
-#include <Library/MemEncryptSevLib.h>
 
 /**
   Install IOMMU protocol to provide the DMA support for PciHostBridge and