patch 8.2.4043: using int for second argument of ga_init2()

Problem:    Using int for second argument of ga_init2().
Solution:   Remove unnessary type cast (int) when using sizeof().
diff --git a/src/evalvars.c b/src/evalvars.c
index 3be9993..d93fed5 100644
--- a/src/evalvars.c
+++ b/src/evalvars.c
@@ -4025,7 +4025,7 @@
     void
 init_redir_ga(void)
 {
-    ga_init2(&redir_ga, (int)sizeof(char), 500);
+    ga_init2(&redir_ga, sizeof(char), 500);
 }
 
 /*