patch 9.0.1158: code is indented more than necessary

Problem:    Code is indented more than necessary.
Solution:   Use an early return where it makes sense. (Yegappan Lakshmanan,
            closes #11787)
diff --git a/src/findfile.c b/src/findfile.c
index 9ce733c..017e1c6 100644
--- a/src/findfile.c
+++ b/src/findfile.c
@@ -1426,11 +1426,11 @@
 {
     // check for NULL pointer, not to return an error to the user, but
     // to prevent a crash
-    if (stack_ptr != NULL)
-    {
-	stack_ptr->ffs_prev = search_ctx->ffsc_stack_ptr;
-	search_ctx->ffsc_stack_ptr = stack_ptr;
-    }
+    if (stack_ptr == NULL)
+	return;
+
+    stack_ptr->ffs_prev = search_ctx->ffsc_stack_ptr;
+    search_ctx->ffsc_stack_ptr = stack_ptr;
 }
 
 /*