Fix user reporting on some custom roms.

the "id" command does not return the username, so just check for root
privileges, and if its not that its system, as no one else could
possibly login

zsh_arm64/system/etc/zsh/zshenv

@@ -11,8 +11,7 @@
 # output or assume the shell is attached to a tty.
 #
 # Global Order: zshenv, zprofile, zshrc, zlogin
-USER=$(id | awk '{print $1}' | grep -Eo '\([a-z]*')
-export USER=${USER[2,99]}
+export USER=$([[ "$(print -P "%#")" == '#' ]] && print 'root' || print 'system')
 export HOME=/data/local/${USER}
 export ANDROID_ROOT=/system
 export ANDROID_DATA=/data