Rollup merge of #32823 - pravic:target-json, r=alexcrichton

Read "is-like-msvc" target option from JSON

This is in reference to #32818.

Author: steveklabnik

src/librustc_back/target/mod.rs

@@ -436,6 +436,7 @@ impl Target {
         key!(target_family, optional);
         key!(is_like_osx, bool);
         key!(is_like_windows, bool);
+        key!(is_like_msvc, bool);
         key!(linker_is_gnu, bool);
         key!(has_rpath, bool);
         key!(no_compiler_rt, bool);