Feat: Add -j flag to control build concurrency

Hilariously enough on my overclocked i9 if I try to build tor with the previously  hardcoded `fmt.Sprintf("-j%d", runtime.NumCPU())` - I get sporadic internal gcc errors.

 This allows passing `-j 16`, which in my case permits me to build tor.

build.go

@@ -25,14 +25,17 @@ var (
  autopointPath string
  folders = []string{"_openssl", "libevent", "zlib", "xz", "tor"}
  absCurrDir = getAbsCurrDir()
- numJobs = fmt.Sprintf("-j%d", runtime.NumCPU())
+ numJobsInt = runtime.NumCPU()
+ numJobs = ""
 )
 
 func main() {
  flag.BoolVar(&verbose, "verbose", false, "Whether to show command output")
  flag.StringVar(&host, "host", "", "Host option, useful for cross-compilation")
  flag.StringVar(&autopointPath, "autopoint-path", "/usr/local/opt/gettext/bin", "OSX: Directory that contains autopoint binary")
+ flag.IntVar(&numJobsInt, "j", runtime.NumCPU(), "Number of jobs to run in parallel")
  flag.Parse()
+ numJobs = fmt.Sprintf("-j%d", numJobsInt)
  if len(flag.Args()) != 1 {
  log.Fatal("Missing command. Can be build-all, build-<folder>, clean-all, clean-<folder>, show-libs, or package-libs")
  }
@@ -206,12 +209,12 @@ func build(folder string) error {
  env = append(env, "LIBS=-lcrypt32 -lgdi32")
  }
  torConf = []string{"sh", "./configure", "--prefix=" + pwd + "/dist",
- "--disable-gcc-hardening", "--disable-system-torrc", "--disable-asciidoc",
+ "--disable-gcc-hardening", "--disable-linker-hardening", "--disable-system-torrc",
  "--enable-static-libevent", "--with-libevent-dir=" + pwd + "/../libevent/dist",
  "--enable-static-openssl", "--with-openssl-dir=" + pwd + "/../_openssl/dist",
  "--enable-static-zlib", "--with-zlib-dir=" + pwd + "/../zlib/dist",
  "--disable-systemd", "--disable-lzma", "--disable-seccomp",
- "--disable-html-manual", "--disable-manpage"}
+ "--disable-html-manual", "--disable-manpage", "--disable-asciidoc"}
 
  if host != "" {
  torConf = append(torConf, "--host="+host)