adjust building from source without LLVM process

The idea here is that the zig2 executable is perhaps the more useful
deliverable until we implement our own optimization passes. This will
allow system packages to provide Zig, and use it to compile Zig
projects, all without LLVM!

ci/x86_64-linux-debug.sh

@@ -24,7 +24,8 @@ git fetch --tags
 git clean -fd
 rm -rf zig-out
 cc -o bootstrap bootstrap.c
-./bootstrap build -Dno-lib
+./bootstrap
+./zig2 build -Dno-lib
 # In order to run these behavior tests we need to move the `@cImport` ones to somewhere else.
 # ./zig-out/bin/zig test test/behavior.zig