[libxml2] Fix inconsistency in xmlXPathIsInf

[Nick Wellnhofer <nwellnhof src gnome org>]

commit ebe12882ee7e14fa6463bb07d7de5f5388f09573
Author: Nick Wellnhofer <wellnhofer aevum de>
Date:   Mon Apr 16 18:18:11 2018 +0200

    Fix inconsistency in xmlXPathIsInf
    
    We don't use HUGE_VAL for INFINITY after the most recent fix.

 xpath.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/xpath.c b/xpath.c
index 89fab58..bd09364 100644
--- a/xpath.c
+++ b/xpath.c
@@ -527,9 +527,9 @@ xmlXPathIsInf(double val) {
 #ifdef isinf
     return isinf(val) ? (val > 0 ? 1 : -1) : 0;
 #else
-    if (val >= HUGE_VAL)
+    if (val >= INFINITY)
         return 1;
-    if (val <= -HUGE_VAL)
+    if (val <= -INFINITY)
         return -1;
     return 0;
 #endif