Fix typo in elf/Makefile:postclean-generated

[Joseph Myers]

The postclean-generated setting in elf/Makefile lists
$(objpfx)/dso-sort-tests-2.generated-makefile twice and
$(objpfx)/dso-sort-tests-1.generated-makefile not at all, which looks
like a typo; fix it to list each once.

Tested for x86_64.

diff --git a/elf/Makefile b/elf/Makefile
index 214c6a9f90..9172d7306e 100644
--- a/elf/Makefile
+++ b/elf/Makefile
@@ -1313,7 +1313,7 @@ $(objpfx)$(1).generated-makefile: $(1)
 endef
 endif
 
-postclean-generated += $(objpfx)/dso-sort-tests-2.generated-makefile \
+postclean-generated += $(objpfx)/dso-sort-tests-1.generated-makefile \
 		       $(objpfx)/dso-sort-tests-2.generated-makefile
 
 # Generate from each testcase description file

-- 
Joseph S. Myers
josmyers@redhat.com