libbacktrace: test --compress-debug-sections=ARG for each ARG
This should fix a testsuite problem with Solaris ld that supports zlib
but not zlib-gabi.
* configure.ac: Test --compress-debug-sections=zlib-gnu and
--compress-debug-sections=zlib-gabi separately, setting new
automake conditionals.
* Makefile.am (ctestg, ctestg_alloc): Only build if
HAVE_COMPRESSED_DEBUG_ZLIB_GNU.
(ctesta, ctesta_alloc): Only build if
HAVE_COMPRESSED_DEBUG_ZLIB_GABI.
(ctestzstd_alloc): New test if HAVE_COMPRESSED_DEBUG_ZSTD.
* configure, Makefile.in: Regenerate.