[ptxdist] [PATCH] ptxd_make_xpkg_pkg.sh: Prevent incomplete comp variable and build break

[Carsten Schlote <carsten.schlote@gmx.net>]

Changed code to detect broken detection of debug compression type. This
prevents an invalid comp variable ('='), which in turn causes some
abort, when objcopy is called with incomplete arguments.

If the compression can't be set and the comp variable is just "=", it
will be set to an empty string. The target objcopy tool will use its
internal default for compression in this case.

Signed-off-by: Carsten Schlote <schlote@vahanus.net>
---
  scripts/lib/ptxd_make_xpkg_pkg.sh | 6 +++++-
  1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/scripts/lib/ptxd_make_xpkg_pkg.sh
b/scripts/lib/ptxd_make_xpkg_pkg.sh
index 08a0ab593..36bb3a564 100644
--- a/scripts/lib/ptxd_make_xpkg_pkg.sh
+++ b/scripts/lib/ptxd_make_xpkg_pkg.sh
@@ -390,11 +390,15 @@ ptxd_install_compression_format() {

      libc="$(ptxd_cross_cc -print-file-name=libc.so.6 2> /dev/null)"
      if [ -n "${libc}" ]; then
-    comp="=$(readelf -t "${libc}" | sed -n -e
'/COMPRESSED/{N;s/.*\(ZLIB\|ZSTD\).*/\1/p;q}' | tr '[:upper:]' '[:lower:]')"
+        comp="=$(readelf -t "${libc}" | sed -n -e
'/COMPRESSED/{N;s/.*\(ZLIB\|ZSTD\).*/\1/p;q}' | tr '[:upper:]' '[:lower:]')"
+    fi
+    if [ "${comp}" == "=" ]; then
+        comp=""
      fi
      export ptxd_install_file_objcopy_args="--only-keep-debug
--compress-debug-sections${comp}"
  }

+
  ptxd_install_compression_format

  ptxd_install_file_extract_debug() {