[xslt] hide "--debug" option when it's disabled

[Alexey Efimov <ave stacksoft ru>]

Hello,

To avoid such situation:

>/onyma/xml/bin/xsltproc --debug b.xsl b.xsl
Unknown option --debug
Usage: /onyma/xml/bin/xsltproc [options] stylesheet file [file ...]
   Options:
        --version or -V: show the version of libxml and libxslt used
        --verbose or -v: show logs of what's happening
        --output file or -o file: save to a given file
        --timing: display the time used
        --repeat: run the transformation 20 times
        --debug: dump the tree of the result instead
        --dumpextensions: dump the registered extension elements and functions to stdout
<skipped>

I offer following small patch against libxslt-1.0.33:

*** xsltproc.old.c      Thu Sep 18 12:58:13 2003
--- xsltproc.c  Thu Sep 18 12:58:50 2003
***************
*** 481,487 ****
--- 481,489 ----
      printf("\t--output file or -o file: save to a given file\n");
      printf("\t--timing: display the time used\n");
      printf("\t--repeat: run the transformation 20 times\n");
+ #ifdef LIBXML_DEBUG_ENABLED
      printf("\t--debug: dump the tree of the result instead\n");
+ #endif
      printf("\t--dumpextensions: dump the registered extension elements and functions to stdout\n");
      printf("\t--novalid skip the Dtd loading phase\n");
      printf("\t--noout: do not dump the result\n");

--
With best regards, Alexey.