Fix -Wempty-body warning from clang

clang recently grew a warning on `for (...);`. This patch
fixes all two instances of this pattern in libxml. The changes
don't modify the code semantic.
diff --git a/pattern.c b/pattern.c
index 0e38c2d..8cd69ae 100644
--- a/pattern.c
+++ b/pattern.c
@@ -305,7 +305,8 @@
     cur->base = pattern;
     if (namespaces != NULL) {
         int i;
-	for (i = 0;namespaces[2 * i] != NULL;i++);
+        for (i = 0;namespaces[2 * i] != NULL;i++)
+            ;
         cur->nb_namespaces = i;
     } else {
         cur->nb_namespaces = 0;
diff --git a/uri.c b/uri.c
index 1ae5768..bd2e96d 100644
--- a/uri.c
+++ b/uri.c
@@ -1604,10 +1604,11 @@
           break;
         }
         /* Valgrind complained, strcpy(cur, segp + 3); */
-	/* string will overlap, do not use strcpy */
-	tmp = cur;
-	segp += 3;
-	while ((*tmp++ = *segp++) != 0);
+        /* string will overlap, do not use strcpy */
+        tmp = cur;
+        segp += 3;
+        while ((*tmp++ = *segp++) != 0)
+          ;
 
         /* If there are no previous segments, then keep going from here.  */
         segp = cur;