libarchive: Cast mode constants to mode_t in case it is signed

At least one compiler (Borland) defines mode_t as just "short" which is
signed.  This breaks code like

  switch(archive_entry_filetype(e)) {
    case AE_IFREG:
    ...
  }

if AE_IFREG and other constants have a longer signed type (int) because
sign extension of the mode_t return type from archive_entry_filetype
changes its value.  Avoid the problem by ensuring the type of the
constants matches mode_t.

This change was originally made in commit a73acfbe (Fix for mode_t with
signed types, 2009-11-07).  Port it to the new libarchive snapshot.

Utilities/cmlibarchive/libarchive/archive_entry.h

@@ -149,14 +149,14 @@ struct archive_entry;
  * portable values to platform-native values when entries are read from
  * or written to disk.
  */
-#define	AE_IFMT		0170000
-#define	AE_IFREG	0100000
-#define	AE_IFLNK	0120000
-#define	AE_IFSOCK	0140000
-#define	AE_IFCHR	0020000
-#define	AE_IFBLK	0060000
-#define	AE_IFDIR	0040000
-#define	AE_IFIFO	0010000
+#define AE_IFMT		((__LA_MODE_T)0170000)
+#define AE_IFREG	((__LA_MODE_T)0100000)
+#define AE_IFLNK	((__LA_MODE_T)0120000)
+#define AE_IFSOCK	((__LA_MODE_T)0140000)
+#define AE_IFCHR	((__LA_MODE_T)0020000)
+#define AE_IFBLK	((__LA_MODE_T)0060000)
+#define AE_IFDIR	((__LA_MODE_T)0040000)
+#define AE_IFIFO	((__LA_MODE_T)0010000)
 
 /*
  * Basic object manipulation