Install a default /etc/default/pcscd file

Fixes systemd warning:
pcscd.service: Referenced but unset environment variable evaluates to an empty string: PCSCD_ARGS

Thanks to iWolf1 for the bug report and idea
" Systemd complains "pcscd.service: Referenced but unset environment
variable evaluates to an empty string: PCSCD_ARGS" #211 "
Fixes: #211

etc/pcscd

@@ -0,0 +1,24 @@
+# Defaults for pcscd (/etc/default/pcscd)
+# https://blog.apdu.fr/posts/2021/08/pcsc-lite-configuration-using/
+
+# PCSCD_ARGS is used in the systemd service unit to pass cli arguments
+# to pcscd executable.
+PCSCD_ARGS = ''
+
+# Set the socket name to talk to remote instance of libpcsclite.so
+# https://blog.apdu.fr/posts/2010/11/pcsc-client-and-server-on-two-different/
+# https://blog.apdu.fr/posts/2022/11/share-smart-card-reader-between-host/
+# https://blog.apdu.fr/posts/2022/02/one-smart-card-reader-accessible-from/
+;PCSCLITE_CSOCK_NAME =
+
+# Adjust USB drivers path at run-time
+;PCSCLITE_HP_DROPDIR = "/usr/lib/pcsc/drivers/"
+
+# Remove and/or customize PC/SC reader names
+# https://blog.apdu.fr/posts/2015/12/remove-andor-customize-pcsc-reader-names/
+;PCSCLITE_FILTER_IGNORE_READER_NAMES = ''
+;PCSCLITE_FILTER_EXTEND_READER_NAMES =
+
+# Do not block on some PC/SC calls
+# https://blog.apdu.fr/posts/2010/05/pcsc-lite-160-new-major-version/
+;PCSCLITE_NO_BLOCKING =

meson.build

@@ -245,6 +245,11 @@ endif
 install_data('etc/fr.apdu.pcsclite.metainfo.xml',
   install_dir : 'share/metainfo'
   )
+
+install_data('etc/pcscd',
+  install_dir : 'etc/default'
+  )
+
 # generate config.h
 configure_file(output : 'config.h',
   configuration : conf_data)