MT#12385 Fix using EXPORT_CONDITIONS

On a stock master CE, running edr exporter results in this error:

$ /usr/sbin/event-exporter
Can't use string ("{ accounting.events.export_statu"...) as an ARRAY ref
while "strict refs" in use at /usr/share/perl5/NGCP/CDR/Exporter.pm line 135.

Reason is that EXPORT_CONDITION only has one element in the default config,
and therefore confval() returns a scalar instead of an array ref. Using
get_config_fields() instead always forces an array we can iterate over.

Change-Id: Id6d049b4275a52dc5760a636472082de625d2ac8

NGCP/CDR/Exporter.pm

@@ -121,7 +121,7 @@ sub get_config {
     @reseller_fields = get_config_fields('RESELLER_EXPORT_FIELDS');
     @data_fields = get_config_fields('DATA_FIELDS');
 
-	foreach my $f(@{confval('EXPORT_JOINS')}) {
+	foreach my $f(get_config_fields('EXPORT_JOINS')) {
 	    $f =~ s/^\s*\{?\s*//; $f =~ s/\}\s*\}\s*$/}/;
 	    my ($a, $b) = split('\s*=>\s*{\s*', $f);
 	    $a =~ s/^\s*\'//; $a =~ s/\'$//g;
@@ -132,7 +132,7 @@ sub get_config {
 	    push @joins, { $a => { $c => $d } };
 	}
 
-	foreach my $f(@{confval('EXPORT_CONDITIONS')}) {
+	foreach my $f(get_config_fields('EXPORT_CONDITIONS')) {
 	    next unless($f);
 	    $f =~ s/^\s*\{?\s*//; $f =~ s/\}\s*\}\s*$/}/;
 	    my ($a, $b) = split('\s*=>\s*{\s*', $f);