Prevent distclean from failing.

e250b274 · Thomas Jahns · 111f2eeb · e250b274
Commit e250b274 authored Apr 23, 2020 by Thomas Jahns 🤸
--- a/inst_headers/Makefile.am
+++ b/inst_headers/Makefile.am
@@ -82,7 +82,7 @@ clean-local:

 distclean-local:
 if ! with_fortran
-	rm f90/Makefile
+	rm -f f90/Makefile
 endif
 	-test "$(abs_builddir)" = "$(abs_srcdir)" || rmdir f90