Fix compiler warnings

Author: cfisoi

ext/libxml/ruby_xml_document.h

@@ -4,7 +4,7 @@
 #define __RXML_DOCUMENT__
 
 extern VALUE cXMLDocument;
-void rxml_init_document();
+void rxml_init_document(void);
 VALUE rxml_document_wrap(xmlDocPtr xnode);
 
 typedef xmlChar * xmlCharPtr;

ext/libxml/ruby_xml_encoding.h

@@ -7,7 +7,7 @@
 
 extern VALUE mXMLEncoding;
 
-void rxml_init_encoding();
+void rxml_init_encoding(void);
 
 VALUE rxml_new_cstr(const xmlChar* xstr, const xmlChar* xencoding);
 VALUE rxml_new_cstr_len(const xmlChar* xstr, const long length, const xmlChar* xencoding);

ext/libxml/ruby_xml_node.c

@@ -781,7 +781,7 @@ static VALUE rxml_node_line_num(VALUE self)
   if (line_num == -1)
     return (Qnil);
   else
-    return (INT2NUM((long) line_num));
+    return (LONG2NUM((long) line_num));
 }
 
 /*

ext/libxml/ruby_xml_parser.h

@@ -5,6 +5,6 @@
 
 extern VALUE cXMLParser;
 
-void rxml_init_parser();
+void rxml_init_parser(void);
 
 #endif

ext/libxml/ruby_xml_parser_options.h

@@ -5,6 +5,6 @@
 
 extern VALUE mXMLParserOptions;
 
-void rxml_init_parser_options();
+void rxml_init_parser_options(void);
 
 #endif

ext/libxml/ruby_xml_reader.c

@@ -1048,7 +1048,7 @@ static VALUE
 rxml_reader_byte_consumed(VALUE self)
 {
   xmlTextReaderPtr xreader = rxml_text_reader_get(self);
-  return INT2NUM(xmlTextReaderByteConsumed(xreader));
+  return LONG2NUM(xmlTextReaderByteConsumed(xreader));
 }
 #endif