perf tools: Create config.detected into OUTPUT directory

Create config.detected into OUTPUT directory instead of source
directory.

This fixes parallel builds that share the same source directory.

Signed-off-by: Aaro Koskinen <[e-mail]>
Acked-by: Jiri Olsa <[e-mail]>
Cc: Paul Mackerras <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/build/Makefile.build

···
 include $(build-dir)/Build.include
 
 # do not force detected configuration
--include .config-detected
+-include $(OUTPUT).config-detected
 
 # Init all relevant variables used in build files so
 # 1) they have correct type

tools/perf/Makefile.perf

···
 clean: $(LIBTRACEEVENT)-clean $(LIBAPI)-clean config-clean
 	$(call QUIET_CLEAN, core-objs)  $(RM) $(LIB_FILE) $(OUTPUT)perf-archive $(OUTPUT)perf-with-kcore $(LANG_BINDINGS)
 	$(Q)find . -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete
-	$(Q)$(RM) .config-detected
+	$(Q)$(RM) $(OUTPUT).config-detected
 	$(call QUIET_CLEAN, core-progs) $(RM) $(ALL_PROGRAMS) perf perf-read-vdso32 perf-read-vdsox32
 	$(call QUIET_CLEAN, core-gen)   $(RM)  *.spec *.pyc *.pyo */*.pyc */*.pyo $(OUTPUT)common-cmds.h TAGS tags cscope* $(OUTPUT)PERF-VERSION-FILE $(OUTPUT)FEATURE-DUMP $(OUTPUT)util/*-bison* $(OUTPUT)util/*-flex*
 	$(QUIET_SUBDIR0)Documentation $(QUIET_SUBDIR1) clean

tools/perf/config/Makefile

···
 obj-perf := $(abspath $(obj-perf))/
 endif
 
-$(shell echo -n > .config-detected)
-detected     = $(shell echo "$(1)=y"       >> .config-detected)
-detected_var = $(shell echo "$(1)=$($(1))" >> .config-detected)
+$(shell echo -n > $(OUTPUT).config-detected)
+detected     = $(shell echo "$(1)=y"       >> $(OUTPUT).config-detected)
+detected_var = $(shell echo "$(1)=$($(1))" >> $(OUTPUT).config-detected)
 
 CFLAGS := $(EXTRA_CFLAGS) $(EXTRA_WARNINGS)