Config.in.legacy: update iostat title

Specify that iostat 'package' has been removed to be consistent with
other entries

Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

Config.in.legacy

@@ -182,7 +182,7 @@ config BR2_PACKAGE_DOCKER_CONTAINERD
 	  The package was renamed to containerd accordingly.
 
 config BR2_PACKAGE_IOSTAT
-	bool "iostat removed"
+	bool "iostat package removed"
 	select BR2_LEGACY
 	help
 	  This package has been removed, use sysstat instead.