BUG/MEDIUM: sample: Fix adjusting size in word converter

Adjust the size of the sample buffer before we change the "area"
pointer. Otherwise, we end up not changing the size, because the area
pointer is already the same as "start" before we compute the difference
between the two.

This is similar to the change in b28430591d18f7fda5bac2e0ea590b3a34f04601
but for the word converter instead of field.

(cherry picked from commit 6a0d2176281bc59e8d81442a056495eb11c5a051)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit e99372925e6207e278740c46e30150fab2b681dc)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/src/sample.c b/src/sample.c
index 9b16621..d9ae4c1 100644
--- a/src/sample.c
+++ b/src/sample.c
@@ -2721,13 +2721,14 @@
 	if (!smp->data.u.str.data)
 		return 1;
 
-	smp->data.u.str.area = start;
 
 	/* Compute remaining size if needed
            Note: smp->data.u.str.size cannot be set to 0 */
 	if (smp->data.u.str.size)
 		smp->data.u.str.size -= start - smp->data.u.str.area;
 
+	smp->data.u.str.area = start;
+
 	return 1;
 }