message: Add debug output for cmake find-package
diff: @@ -232,15 +232,16 @@ impl<'r> CmakeProbe<'r> {
  let mut include_paths = Vec::with_capacity(2);
  let mut link_paths = Vec::with_capacity(2);
  let mut link_libs = Vec::with_capacity(64);
  - self.make_cmd()
  - .args(&[
  + let mut cmd = self.make_cmd();
  + cmd.args(&[
  "--find-package",
  "-DCOMPILER_ID=GNU",
  "-DLANGUAGE=CXX",
  "-DMODE=COMPILE",
  ])
  - .arg(format!("-DNAME={}", self.package_name))
  - .output()
  + .arg(format!("-DNAME={}", self.package_name));
  + eprintln!("=== cmake find-package compile probe command: {:?}", cmd);
  + cmd.output()
  .map_err(Box::<dyn std::error::Error>::from)
  .and_then(|output| if output.status.success() {
  let stdout = String::from_utf8(output.stdout)?;
  @@ -255,15 +256,16 @@ impl<'r> CmakeProbe<'r> {
  ).into())
  })?;
  - self.make_cmd()
  - .args(&[
  + cmd = self.make_cmd();
  + cmd.args(&[
  "--find-package",
  "-DCOMPILER_ID=GNU",
  "-DLANGUAGE=CXX",
  "-DMODE=LINK",
  ])
  - .arg(format!("-DNAME={}", self.package_name))
  - .output()
  + .arg(format!("-DNAME={}", self.package_name));
  + eprintln!("=== cmake find-package link probe command: {:?}", cmd);
  + cmd.output()
  .map_err(Box::<dyn std::error::Error>::from)
  .and_then(|output| if output.status.success() {
  let stdout = String::from_utf8(output.stdout)?;
  