Add AsciiSPrint()

AsciiSPrint() is really snprintf(), but gnu-efi has a different naming
convention.

Signed-off-by: Peter Jones <pjones@redhat.com>

inc/efilib.h

@@ -596,6 +596,14 @@ AsciiVSPrint(
     __builtin_ms_va_list args
 );
 
+UINTN EFIAPI
+AsciiSPrint (
+    OUT CHAR8         *Str,
+    IN UINTN          StrSize,
+    IN CONST CHAR8    *fmt,
+    ...
+    );
+
 VOID
 ValueToHex (
     IN CHAR16   *Buffer,

lib/print.c

@@ -899,6 +899,43 @@ Returns:
     return Len;
 }
 
+UINTN EFIAPI
+AsciiSPrint (
+    OUT CHAR8         *Str,
+    IN UINTN          StrSize,
+    IN CONST CHAR8    *fmt,
+    ...
+    )
+/*++
+
+Routine Description:
+
+    Prints a formatted unicode string to a buffer
+
+Arguments:
+
+    Str         - Output buffer to print the formatted string into
+
+    StrSize     - Size of Str.  String is truncated to this size.
+                  A size of 0 means there is no limit
+
+    fmt         - The format string
+
+Returns:
+
+    String length returned in buffer
+
+--*/
+{
+    ms_va_list       args;
+    UINTN            len;
+
+    ms_va_start (args, fmt);
+    len = AsciiVSPrint(Str, StrSize, fmt, args);
+    ms_va_end (args);
+
+    return len;
+}
 
 STATIC
 VOID