gnu: Use 'search-input-directory' when looking for tzdata.

* gnu/packages/backup.scm (duplicity)[arguments]: Use
'search-input-directory' for "share/zoneinfo".
* gnu/packages/bioinformatics.scm (pigx-rnaseq): Likewise.
(pigx-bsseq): Likewise.
* gnu/packages/calcurse.scm (calcurse): Likewise.
* gnu/packages/calendar.scm (date): Likewise.
* gnu/packages/compression.scm (lhasa): Likewise.
* gnu/packages/cran.scm (r-rstan): Likewise.
* gnu/packages/django.scm (python-django): Likewise.
* gnu/packages/dlang.scm (ldc-bootstrap): Likewise.
* gnu/packages/finance.scm (ledger): Likewise.
* gnu/packages/glib.scm (glib): Likewise.
* gnu/packages/golang.scm (go-1.4): Likewise.
(go-1.14): Likewise.
* gnu/packages/kde-frameworks.scm (kcalendarcore): Likewise.
(kdelibs4support): Likewise.
* gnu/packages/kodi.scm (kodi): Likewise.
* gnu/packages/mail.scm (mu): Likewise.
* gnu/packages/perl.scm (perl-libtime-parsedate): Likewise.
* gnu/packages/python-xyz.scm (python-robotframework): Likewise.
(python-dparse): Likewise.
* gnu/packages/rrdtool.scm (rrdtool): Likewise.
* gnu/packages/statistics.scm (r-with-tests): Likewise.
* gnu/packages/vim.scm (vim): Likewise.
* gnu/packages/virtualization.scm (ganeti): Likewise.
* gnu/packages/vpn.scm (strongswan): Likewise.
* gnu/packages/xfce.scm (xfce4-panel): Likewise.
* gnu/packages/mate.scm (libmateweather): Use 'search-input-file' for
"share/zoneinfo/zone.tab".

gnu/packages/virtualization.scm

@@ -598,8 +598,7 @@ server and embedded PowerPC, and S390 guests.")
          (add-before 'check 'pre-check
            (lambda* (#:key inputs #:allow-other-keys)
              ;; Set TZDIR so that time zones are found.
-             (setenv "TZDIR" (string-append (assoc-ref inputs "tzdata")
-                                            "/share/zoneinfo"))
+             (setenv "TZDIR" (search-input-directory inputs "share/zoneinfo"))
 
              (substitute* "test/py/ganeti.utils.process_unittest.py"
                ;; This test attempts to run an executable with