tools build: Make test-rust.bin be removed by the 'clean' target

test-rust.bin is missing from the list of FILES, and thus is not removed by the
clean target. This could lead to a false feature detection, since the binary
stays there. Fix it.

Fixes: 6a32fa5 ("tools build: Add a feature test for rust compiler")
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Dmitrii Dolgov <9erthalion6@gmail.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

Author: erthalion

tools/build/feature/Makefile

@@ -73,6 +73,7 @@ FILES=                                          \
          test-clang-bpf-co-re.bin		\
          test-file-handle.bin			\
          test-libpfm4.bin			\
+         test-rust.bin				\
          test-libopenssl.bin
 
 FILES := $(addprefix $(OUTPUT),$(FILES))