CLEANUP: opentracing: removed unused function flt_ot_var_unset()

The flt_ot_var_unset() function is not used anywhere and is unnecessary
in the existing implementation of the OpenTracing filter.

This patch must be backported as far as 2.4.

(cherry picked from commit e40a34cea13b236261ae75940390da5ef4e66247)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit e938f075b7440f78eb0c44fe6bf7f84f9aced993)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
2 files changed