OvmfPkg/XenBusDxe: Add an helper AsciiStrDup.

.. because we need it in the patch titled:
"OvmfPkg/XenBusDxe: Introduce XenBus support itself."

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@16268 6f19259b-4bc3-4df7-8a09-765794883524

OvmfPkg/XenBusDxe/Helpers.c

@@ -0,0 +1,9 @@
+#include "XenBusDxe.h"
+
+CHAR8*
+AsciiStrDup (
+  IN CONST CHAR8* Str
+  )
+{
+  return AllocateCopyPool (AsciiStrSize (Str), Str);
+}

OvmfPkg/XenBusDxe/XenBusDxe.h

@@ -116,4 +116,9 @@ TestAndClearBit (
   IN volatile VOID *Address
   );
 
+CHAR8*
+AsciiStrDup (
+  IN CONST CHAR8* Str
+  );
+
 #endif