stretch+: default to en_US, ones less keyboard click as there are no options

Signed-off-by: Robert Nelson <robertcnelson@gmail.com>

lib/buster-preseed.cfg

@@ -1,9 +1,12 @@
 #From: https://www.debian.org/releases/buster/example-preseed.txt
+#### Contents of the preconfiguration file (for buster)
+### Localization
+# Preseeding only locale sets language, country and locale.
+d-i debian-installer/locale string en_US
 
 # The Wheezy, USB disabled (no keyboard access) till after you select keymap bug...
 #(this is not needed in serial mode)
 #d-i console-tools/archs string skip-config
-#d-i debian-installer/locale string en_US
 #d-i console-keymaps-at/keymap select us
 
 #Removes the prompt about missing modules:

lib/stretch-preseed.cfg

@@ -1,9 +1,12 @@
 #From: https://www.debian.org/releases/buster/example-preseed.txt
+#### Contents of the preconfiguration file (for buster)
+### Localization
+# Preseeding only locale sets language, country and locale.
+d-i debian-installer/locale string en_US
 
 # The Wheezy, USB disabled (no keyboard access) till after you select keymap bug...
 #(this is not needed in serial mode)
 #d-i console-tools/archs string skip-config
-#d-i debian-installer/locale string en_US
 #d-i console-keymaps-at/keymap select us
 
 #Removes the prompt about missing modules: