sci-libs/blas-lapack-aux-wrapper: only allow bfd or lld

mold doesn't implement required functionality. I've not bothered w/
BDEPEND or a pkg_* check given a mold-only system seems pretty unlikely,
but may need to change that in future.

Closes: https://bugs.gentoo.org/965199
Signed-off-by: Sam James <sam@gentoo.org>

sci-libs/blas-lapack-aux-wrapper/blas-lapack-aux-wrapper-1.ebuild

@@ -40,6 +40,11 @@ BDEPEND="
 QA_FLAGS_IGNORED=".*"
 
 src_configure() {
+	# We rely on some specific linker features (bug #965199)
+	if ! tc-ld-is-bfd && ! tc-ld-is-lld; then
+		tc-ld-force-bfd
+	fi
+
 	local emesonargs=(
 		-Dilp64=$(usex index64 true false)
 	)