perf build: Move feature cleanup under tools/build

Arnaldo reported issue for following build command:

  $ rm -rf /tmp/krava; mkdir /tmp/krava; make O=/tmp/krava clean
    CLEAN    config
  /bin/sh: line 0: cd: /tmp/krava/feature/: No such file or directory
  ../../scripts/Makefile.include:17: *** output directory "/tmp/krava/feature/" does not exist.  Stop.
  make[1]: *** [Makefile.perf:1010: config-clean] Error 2
  make: *** [Makefile:90: clean] Error 2

The problem is that now that we include scripts/Makefile.include
in feature's Makefile (which is fine and needed), we need to ensure
the OUTPUT directory exists, before executing (out of tree) clean
command.

Removing the feature's cleanup from perf Makefile and fixing
feature's cleanup under build Makefile, so it now checks that
there's existing OUTPUT directory before calling the clean.

Fixes: 211a741 ("tools: Factor Clang, LLC and LLVM utils definitions")
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # LLVM/Clang v13-git
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20210224150831.409639-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/build/Makefile

@@ -30,12 +30,18 @@ build     := -f $(srctree)/tools/build/Makefile.build dir=. obj
 
 all: $(OUTPUT)fixdep
 
+# Make sure there's anything to clean,
+# feature contains check for existing OUTPUT
+TMP_O := $(if $(OUTPUT),$(OUTPUT)/feature,./)
+
 clean:
 	$(call QUIET_CLEAN, fixdep)
 	$(Q)find $(if $(OUTPUT),$(OUTPUT),.) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete
 	$(Q)rm -f $(OUTPUT)fixdep
 	$(call QUIET_CLEAN, feature-detect)
-	$(Q)$(MAKE) -C feature/ clean >/dev/null
+ifneq ($(wildcard $(TMP_O)),)
+	$(Q)$(MAKE) -C feature OUTPUT=$(TMP_O) clean >/dev/null
+endif
 
 $(OUTPUT)fixdep-in.o: FORCE
 	$(Q)$(MAKE) $(build)=fixdep

tools/perf/Makefile.perf

@@ -1001,14 +1001,6 @@ $(INSTALL_DOC_TARGETS):
 
 ### Cleaning rules
 
-#
-# This is here, not in Makefile.config, because Makefile.config does
-# not get included for the clean target:
-#
-config-clean:
-	$(call QUIET_CLEAN, config)
-	$(Q)$(MAKE) -C $(srctree)/tools/build/feature/ $(if $(OUTPUT),OUTPUT=$(OUTPUT)feature/,) clean >/dev/null
-
 python-clean:
 	$(python-clean)
 
@@ -1048,7 +1040,7 @@ endif # BUILD_BPF_SKEL
 bpf-skel-clean:
 	$(call QUIET_CLEAN, bpf-skel) $(RM) -r $(SKEL_TMP_OUT) $(SKELETONS)
 
-clean:: $(LIBTRACEEVENT)-clean $(LIBAPI)-clean $(LIBBPF)-clean $(LIBSUBCMD)-clean $(LIBPERF)-clean config-clean fixdep-clean python-clean bpf-skel-clean
+clean:: $(LIBTRACEEVENT)-clean $(LIBAPI)-clean $(LIBBPF)-clean $(LIBSUBCMD)-clean $(LIBPERF)-clean fixdep-clean python-clean bpf-skel-clean
 	$(call QUIET_CLEAN, core-objs)  $(RM) $(LIBPERF_A) $(OUTPUT)perf-archive $(OUTPUT)perf-with-kcore $(LANG_BINDINGS)
 	$(Q)find $(if $(OUTPUT),$(OUTPUT),.) -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete
 	$(Q)$(RM) $(OUTPUT).config-detected