archive/ArchiveLookup: remove "suffix" output parameter

Let the caller do this.  Our GetSuffix() function was broken anyway.

src/archive/ArchiveLookup.cxx

@@ -36,21 +36,9 @@ FindSlash(char *p, size_t i) noexcept
 	return nullptr;
 }
 
-gcc_pure
-static const char *
-FindSuffix(const char *p, const char *i) noexcept
-{
-	for (; i > p; --i) {
-		if (*i == '.')
-			return i + 1;
-	}
-
-	return nullptr;
-}
-
 bool
 archive_lookup(char *pathname, const char **archive,
-	       const char **inpath, const char **suffix)
+	       const char **inpath)
 {
 	size_t idx = strlen(pathname);
 
@@ -70,9 +58,6 @@ archive_lookup(char *pathname, const char **archive,
 				//so the upper should be file
 				*archive = pathname;
 				*inpath = slash + 1;
-
-				//try to get suffix
-				*suffix = FindSuffix(pathname, slash - 1);
 				return true;
 			} else {
 				FormatError(archive_domain,

src/archive/ArchiveLookup.hxx

@@ -24,24 +24,23 @@
  *
  * archive_lookup is used to determine if part of pathname refers to an regular
  * file (archive). If so then its also used to split pathname into archive file
- * and path used to locate file in archive. It also returns suffix of the file.
+ * and path used to locate file in archive.
  * How it works:
  * We do stat of the parent of input pathname as long as we find an regular file
  * Normally this should never happen. When routine returns true pathname modified
- * and split into archive, inpath and suffix. Otherwise nothing happens
+ * and split into archive and inpath. Otherwise nothing happens
  *
  * For example:
  *
  * /music/path/Talco.zip/Talco - Combat Circus/12 - A la pachenka.mp3
  * is split into archive:	/music/path/Talco.zip
  * inarchive pathname:		Talco - Combat Circus/12 - A la pachenka.mp3
- * and suffix:			 zip
  *
  * Throws on error.
  */
 bool
 archive_lookup(char *pathname, const char **archive,
-	       const char **inpath, const char **suffix);
+	       const char **inpath);
 
 #endif