build: clean up .dwo files

Makefile.in

Index: Makefile.in
diff --git a/Makefile.in b/Makefile.in
index 97ef571902ec26ec726bd3b52c099009f2434e63..dee8fea65ee4d43fdca0299141da7b48e73f29a1 100644
--- a/Makefile.in
+++ b/Makefile.in
@@ -8981,7 +8981,8 @@ maintainer-clean-am: distclean-am maintainer-clean-generic
 
 mostlyclean: mostlyclean-am
 
-mostlyclean-am: mostlyclean-compile mostlyclean-generic
+mostlyclean-am: mostlyclean-compile mostlyclean-generic \
+	mostlyclean-local
 
 pdf: pdf-am
 
@@ -9022,8 +9023,8 @@ uninstall-am: uninstall-binPROGRAMS uninstall-dist_docDATA \
 	install-pdf-am install-pkgconfigDATA install-ps install-ps-am \
 	install-strip installcheck installcheck-am installdirs \
 	maintainer-clean maintainer-clean-generic mostlyclean \
-	mostlyclean-compile mostlyclean-generic pdf pdf-am ps ps-am \
-	recheck tags tags-am uninstall uninstall-am \
+	mostlyclean-compile mostlyclean-generic mostlyclean-local pdf \
+	pdf-am ps ps-am recheck tags tags-am uninstall uninstall-am \
 	uninstall-binPROGRAMS uninstall-dist_docDATA \
 	uninstall-includecHEADERS uninstall-includeclHEADERS \
 	uninstall-includeclcHEADERS uninstall-includecldwcHEADERS \
@@ -9035,6 +9036,9 @@ uninstall-am: uninstall-binPROGRAMS uninstall-dist_docDATA \
 .PRECIOUS: Makefile
 
 
+mostlyclean-local:
+	-find src -name '*.dwo' -exec rm -f {} +
+
 # Tell versions [3.59,3.63) of GNU make to not export all variables.
 # Otherwise a system limit (for SysV at least) may be exceeded.
 .NOEXPORT: