REGTESTS: connection: disable http_reuse_be_transparent.vtc if !TPROXY

http_reuse_be_transparent.vtc relies on "transparent" proxy option which
is guarded by the USE_TPROXY ifdef at multiple places in the code.

Hence, executing the above test when haproxy was compiled without the
USE_TPROXY feature (ie: generic target) results in this kind of error:

  ***  h1    debug|[NOTICE]   (1189756) : haproxy version is 2.9-dev1-8fc21e-807
  ***  h1    debug|[NOTICE]   (1189756) : path to executable is ./haproxy
  ***  h1    debug|[ALERT]    (1189756) : config : parsing [/tmp/vtc.1189751.18665e7b/h1/cfg:11]: option 'transparent' is not supported due to build options.
  ***  h1    debug|[ALERT]    (1189756) : config : Error(s) found in configuration file : /tmp/vtc.1189751.18665e7b/h1/cfg

Now we skip the regtest if TPROXY feature is missing.

(cherry picked from commit 3a1b8ad1b5d1edcfb72d53c6818cd5ad6d5a45f2)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit 703bcae0537dc774f3bf99ab40c805bf2b470754)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit 42066d06dd95db9de94df1db9e896a704355dcf6)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit 8752a562b024081b0cd000946efa6aa944cb8ee9)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/reg-tests/connection/http_reuse_be_transparent.vtc b/reg-tests/connection/http_reuse_be_transparent.vtc
index 1cadb35..3fb9e7a 100644
--- a/reg-tests/connection/http_reuse_be_transparent.vtc
+++ b/reg-tests/connection/http_reuse_be_transparent.vtc
@@ -1,4 +1,5 @@
 varnishtest "Test the proper interaction between http-reuse and backend in transparent mode"
+feature cmd "$HAPROXY_PROGRAM -cc 'feature(TPROXY)'"
 
 # If backend is used with the transparent mode, the connection are considered
 # as private and should only be reused for requests of the same session.