COMP: Use HAVE_SYS_PARAM_H properly in libtar

The value is computed by a try-compile for libtar.  This teaches the
sources to actually use the result.

Utilities/cmtar/append.c

@@ -18,7 +18,9 @@
 #if defined(_WIN32) && !defined(__CYGWIN__)
 # include <libtar/compat.h>
 #else
-# include <sys/param.h>
+# ifdef HAVE_SYS_PARAM_H
+#  include <sys/param.h>
+# endif
 #endif
 #include <libtar/compat.h>
 #include <sys/types.h>

Utilities/cmtar/decode.c

@@ -17,7 +17,9 @@
 #if defined(_WIN32) && !defined(__CYGWIN__)
 # include <libtar/compat.h>
 #else
-# include <sys/param.h>
+# ifdef HAVE_SYS_PARAM_H
+#  include <sys/param.h>
+# endif
 #endif
 
 #ifndef WIN32

Utilities/cmtar/extract.c

@@ -28,7 +28,9 @@
 # include <direct.h>
 #else
 # include <utime.h>
-# include <sys/param.h>
+# ifdef HAVE_SYS_PARAM_H
+#  include <sys/param.h>
+# endif
 #endif
 
 #ifdef STDC_HEADERS

Utilities/cmtar/libtar.c

@@ -19,7 +19,9 @@
 #include <libtar/compat.h>
 #include <io.h>
 #else
-#include <sys/param.h>
+# ifdef HAVE_SYS_PARAM_H
+#  include <sys/param.h>
+# endif
 #endif
 
 #ifdef STDC_HEADERS

Utilities/cmtar/util.c

@@ -23,7 +23,9 @@
 #if defined(_WIN32) && !defined(__CYGWIN__)
 #include <direct.h>
 #else
-#include <sys/param.h>
+# ifdef HAVE_SYS_PARAM_H
+#  include <sys/param.h>
+# endif
 #endif
 
 /* hashing function for pathnames */

Utilities/cmtar/wrapper.c

@@ -17,7 +17,7 @@
 
 #include <libtar/compat.h>
 #if defined(HAVE_SYS_PARAM_H)
-#include <sys/param.h>
+# include <sys/param.h>
 #endif
 #if defined(HAVE_DIRENT_H)
 #include <dirent.h>