Fix clash when enabling lib32 and lib64 at same time, backport from:
https://sourceforge.net/p/mingw-w64/mingw-w64/ci/953bcd32ae470c4647e94de8548dda5a8f07d82d/
(except directly to Makefile.in to avoid autoreconf over this)
--- a/mingw64/mingw-w64-crt/Makefile.in
+++ b/mingw64/mingw-w64-crt/Makefile.in
@@ -153,3 +153,3 @@
 host_triplet = @host@
-@DLLTOOL_HAS_TEMP_PREFIX_TRUE@am__append_1 = --temp-prefix $$(basename $@ .a)
+@DLLTOOL_HAS_TEMP_PREFIX_TRUE@am__append_1 = --temp-prefix $(basename $@)
 @DELAY_IMPORT_LIBS_TRUE@am__append_2 = --output-delaylib $@.delayimp.a