subparse: Remove dependency on regex.h as it's not used anyway

Fixes bug #592544.

configure.ac

@@ -154,14 +154,9 @@ dnl used in gst/ffmpegcolorspace/mem.c
 dnl FIXME: could be fixed by redefining av_malloc and av_free to GLib's
 AC_CHECK_HEADERS([malloc.h])
 
-dnl used in gst/subparse/gstsubparse.c
-AC_CHECK_HEADERS([regex.h], HAVE_REGEX_H="yes", HAVE_REGEX_H="no")
-AM_CONDITIONAL(HAVE_REGEX_H, test "x$HAVE_REGEX_H" = "xyes")
-
-if test "x$HAVE_REGEX_H" = "xyes"; then
-  ac_cppflags_save="$CPPFLAGS"
-  CPPFLAGS="`$PKG_CONFIG --cflags libxml-2.0`"
-  AC_COMPILE_IFELSE(
+ac_cppflags_save="$CPPFLAGS"
+CPPFLAGS="`$PKG_CONFIG --cflags libxml-2.0`"
+AC_COMPILE_IFELSE(
   AC_LANG_PROGRAM([
 #include <libxml/HTMLparser.h>
                      ],[
@@ -169,10 +164,7 @@ if test "x$HAVE_REGEX_H" = "xyes"; then
 #error libxml2 has no HTML support
 #endif /* LIBXML_HTML_ENABLED */
                    ]), HAVE_LIBXML_HTML="yes", HAVE_LIBXML_HTML="no")
-  CPPFLAGS="$ac_cppflags_save"
-else
-  HAVE_LIBXML_HTML="no"
-fi
+CPPFLAGS="$ac_cppflags_save"
 AM_CONDITIONAL(HAVE_LIBXML_HTML, test "x$HAVE_LIBXML_HTML" = "xyes")
 
 dnl used in gst/tcp

gst/subparse/gstsubparse.c

@@ -27,7 +27,6 @@
 #include <stdlib.h>
 #include <sys/types.h>
 #include <glib.h>
-#include <regex.h>
 
 #include "gstsubparse.h"
 #include "gstssaparse.h"