Fix small matters and improve sysconf()

- Fix mkdeps.com out of memory error
- Remove static memory from __get_cpu_count()
- Add support for passing hyphen to cat in cocmd
- Change more ZipOS errors from ENOTSUP to EROFS
- Specify mem_unit in sysinfo() output on BSD OSes

third_party/radpajama/common-gptneox.cc

@@ -39,7 +39,7 @@
 // clang-format off
 
 bool gpt_params_parse(int argc, char ** argv, gpt_params & params) {
-    params.n_threads = std::min(20, std::max(1, (int)(_getcpucount() * 0.75)));
+    params.n_threads = std::min(20., (unsigned)__get_cpu_count() * 0.75);
 
     bool invalid_param = false;
     std::string arg;