lttng-tools-2.14.0-rc1: fails to compile with libxml2-2.14.4

[Norbert Lange]

/tmp/dev_develop_libxml2/usr/include/libxml2/libxml/encoding.h:173:7:
note: declared here
  173 |     } input XML_DEPRECATED_MEMBER;
      |       ^~~~~
../../../src/common/config/session-config.cpp:297:75: error: no match
for call to '(_xmlCharEncodingHandler::<unnamed union>) (xmlChar*&,
int*, const xmlChar*, int*)'
  297 |  ret = handler->input(out_str, &out_len, (const xmlChar *)
in_str, &in_len);
      |
           ^

Changing the call to handler->input.legacyFunc seems to fix it.

Also lttng seems to need libxml2, but doesnt add the necessary flags.

Regards, Norbert