Use C.UTF-8 to match upstream

setup/linux/profile/airootfs/etc/locale.conf

@@ -1 +1 @@
-LANG=en_US.UTF-8
+LANG=C.UTF-8

setup/linux/profile/airootfs/etc/pacman.d/hooks/40-locale-gen.hook

@@ -1,13 +0,0 @@
-# remove from airootfs!
-[Trigger]
-Operation = Install
-Type = Package
-Target = glibc
-
-[Action]
-Description = Uncommenting en_US.UTF-8 locale and running locale-gen...
-When = PostTransaction
-Depends = glibc
-Depends = sed
-Depends = sh
-Exec = /bin/sh -c "sed -i 's/#\(en_US\.UTF-8\)/\1/' /etc/locale.gen && locale-gen"