Fix build with Perl 5.25.

Braces should be escaped in regexps.

With hat:	perl@
Sponsored by:	Absolight

textproc/p5-XML-Twig/files/patch-speedup

@@ -0,0 +1,11 @@
+--- speedup.orig	2014-06-11 07:23:43 UTC
++++ speedup
+@@ -12,7 +12,7 @@ my $SET_NOT_EMPTY= join( '|', qw( pcdata
+ # depending on the version of perl use either qr or ""
+ print STDERR "perl version is $]\n";
+ 
+-my $var= '(\$[a-z_]+(?:\[\d\])?|\$t(?:wig)?->root|\$t(?:wig)?->twig_current|\$t(?:wig)?->{\'?twig_root\'?}|\$t(?:wig)?->{\'?twig_current\'?})';
++my $var= '(\$[a-z_]+(?:\[\d\])?|\$t(?:wig)?->root|\$t(?:wig)?->twig_current|\$t(?:wig)?->\{\'?twig_root\'?}|\$t(?:wig)?->\{\'?twig_current\'?})';
+ 
+ my $set_to = '(?:undef|\$\w+|\$\w+->\{\w+\}|\$\w+->\w+|\$\w+->\w+\([^)]+\))';
+ my $elt    = '\$(?:elt|new_elt|child|cdata|ent|_?parent|twig_current|next_sibling|first_child|prev_sibling|last_child|ref|elt->_parent)';