Log message:
Pullup ticket #6459 - requested by nia
textproc/libxslt: build fix

Revisions pulled up:
- textproc/libxslt/distinfo                                     1.66
- textproc/libxslt/patches/patch-configure                      1.3

---
   Module Name:	pkgsrc
   Committed By:	mcf
   Date:		Mon May 24 04:18:19 UTC 2021

   Modified Files:
   	pkgsrc/textproc/libxslt: distinfo
   Added Files:
   	pkgsrc/textproc/libxslt/patches: patch-configure

   Log message:
   libxslt: fix libxml2 detection with libxml2 >= 2.9.11

   xml2-config from libxml2 >= 2.9.11 now exits with non-zero status
   for invalid arguments. libxslt called xml2-config with the invalid
   `print` option to probe for its existence, so with new libxml2 it
   now skipped detection via xml2-config entirely causing a build
   failure.

   Apply upstream patch to correct this invalid xml2-config usage.