thought that an uncompressed .debug_str section was compressed.
* compress.c (bfd_is_section_compressed): When checking the
.debug_str section, also check the fifth byte in the section is
not part of a string.
* binutils-all/debug_str.s: New test.
* binutils-all/debug_str.d: New test control file.
* binutils-all/compress.exp: Run debug_str test.
