stdenv-setup: Add quotes that don't do anything for consistency.
stdenv-setup: Add quotes that don't do anything for consistency.

@vcunat and others rightly point out that it's easier to quote always,
than learn Bash's idiosyncrasies enough to know when it doesn't make a
difference.

This reverts commit 2743078f664ae07c4bed06a96182c6a86bd7fa32, which
removes quotes that don't do anything, and then goes further adding
even more quotes.

SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,NixOS/nixpkgs,SymbiFlow/nixpkgs