Re-enable all inline asm usage for the rustc tests

scripts/setup_rust_fork.sh

@@ -13,23 +13,6 @@ git checkout "$(rustc -V | cut -d' ' -f3 | tr -d '(')"
 git -c user.name=Dummy -c user.email=dummy@example.com -c commit.gpgSign=false \
     am ../patches/*-stdlib-*.patch
 
-git apply - <<EOF
-diff --git a/library/alloc/Cargo.toml b/library/alloc/Cargo.toml
-index d95b5b7f17f..00b6f0e3635 100644
---- a/library/alloc/Cargo.toml
-+++ b/library/alloc/Cargo.toml
-@@ -8,7 +8,7 @@ edition = "2018"
-
- [dependencies]
- core = { path = "../core" }
--compiler_builtins = { version = "0.1.40", features = ['rustc-dep-of-std'] }
-+compiler_builtins = { version = "0.1.66", features = ['rustc-dep-of-std', 'no-asm'] }
-
- [dev-dependencies]
- rand = { version = "0.8.5", default-features = false, features = ["alloc"] }
- rand_xorshift = "0.3.0"
-EOF
-
 cat > config.toml <<EOF
 change-id = 115898
 
@@ -49,9 +32,6 @@ verbose-tests = false
 EOF
 popd
 
-# FIXME remove once inline asm is fully supported
-export RUSTFLAGS="$RUSTFLAGS --cfg=rustix_use_libc"
-
 export CFG_VIRTUAL_RUST_SOURCE_BASE_DIR="$(cd build/stdlib; pwd)"
 
 # Allow the testsuite to use llvm tools