configs/basic-pbx/asterisk.conf: contains incorrect path separator

Note: When packagers use these files (as an example) the paths are never
really used when they are split using '='.

Note: Thirdparty applications will also have trouble parsing the file when
expecting '=>'.

Change-Id: I0ada647f588e81f023fb1333ca15a1a333fd6004

configs/basic-pbx/asterisk.conf

 [directories]
-astetcdir = /etc/asterisk
-astmoddir = /usr/lib/asterisk/modules
-astvarlibdir = /var/lib/asterisk
-astdbdir = /var/lib/asterisk
-astkeydir = /var/lib/asterisk
-astdatadir = /var/lib/asterisk
-astagidir = /var/lib/asterisk/agi-bin
-astspooldir = /var/spool/asterisk
-astrundir = /var/run/asterisk
-astlogdir = /var/log/asterisk
-astsbindir = /usr/sbin
+astetcdir => /etc/asterisk
+astmoddir => /usr/lib/asterisk/modules
+astvarlibdir => /var/lib/asterisk
+astdbdir => /var/lib/asterisk
+astkeydir => /var/lib/asterisk
+astdatadir => /var/lib/asterisk
+astagidir => /var/lib/asterisk/agi-bin
+astspooldir => /var/spool/asterisk
+astrundir => /var/run/asterisk
+astlogdir => /var/log/asterisk
+astsbindir => /usr/sbin
 
 [options]
 ; If we want to start Asterisk with a default verbosity for the verbose