Fix Intel compiler warnings on Windows in cmtar

This commit disables or fixes some warnings in the 'cmtar' utility
produced by the Intel compiler on Windows.

Utilities/cmtar/compat/fnmatch.c

@@ -174,12 +174,7 @@ fnmatch(pattern, string, flags)
   /* NOTREACHED */
 }
 
-static int
-rangematch(pattern, test, flags, newp)
-  const char *pattern;
-  char test;
-  int flags;
-  char **newp;
+static int rangematch(const char *pattern, char test, int flags, char **newp)
 {
   int negate, ok;
   char c, c2;

Utilities/cmtar/compat/snprintf.c

@@ -42,6 +42,10 @@
 
 #include <libtar/config.h>
 
+#if defined(__INTEL_COMPILER)
+# pragma warning disable 177 /* function declared but not referenced */
+#endif
+
 #if !defined(HAVE_SNPRINTF) || !defined(HAVE_VSNPRINTF)
 
 #include <stdio.h>

Utilities/cmtar/libtar.c

@@ -312,7 +312,7 @@ extract(char *tarfile, char *rootdir)
   return 0;
 }
 
-
+#if !defined(_WIN32) || defined(__CYGWIN__)
 static void
 usage()
 {
@@ -322,7 +322,7 @@ usage()
          progname);
   exit(-1);
 }
-
+#endif
 
 #define MODE_LIST  1
 #define MODE_CREATE  2