Move condcodes.rs to a new crate, cranelift-codegen-shared

This move allows the `IntCC`/`FloatCC` enums to be used in both meta (for predicate matching) and in codegen. To avoid breaking any code dependent on the previous location of condcodes.rs (`cranelift-codegen/src/condcodes.rs`), the module is re-exported under `cranelift_codegen::ir`.

cranelift/publish-all.sh

@@ -15,7 +15,7 @@ version="0.43.1"
 #
 # The main Cargo.toml in the top-level directory is the cranelift-tools crate which we don't publish.
 echo "Updating crate versions to $version"
-for crate in . cranelift-* cranelift-codegen/meta; do
+for crate in . cranelift-* cranelift-codegen/shared cranelift-codegen/meta; do
     # Update the version number of this crate to $version.
     sed -i.bk -e "s/^version = .*/version = \"$version\"/" \
         "$crate/Cargo.toml"
@@ -38,7 +38,7 @@ echo git tag v$version
 echo git push
 echo git push origin v$version
 for crate in \
-    entity bforest codegen/meta codegen frontend native \
+    entity bforest codegen/shared codegen/meta codegen frontend native \
     preopt \
     reader wasm module \
     faerie umbrella simplejit