perf build: Remove PERF-CFLAGS file

Removing PERF-CFLAGS file, because the build framework stores full build
command line for each object and triggers rebuilt if necessary.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Tested-by: Will Deacon <will.deacon@arm.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-99hamnd2msiwgsi78yauihhd@git.kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Makefile.perf

@@ -365,7 +365,7 @@ LIBTRACEEVENT_FLAGS  = $(QUIET_SUBDIR1) O=$(OUTPUT)
 LIBTRACEEVENT_FLAGS += CFLAGS="-g -Wall $(EXTRA_CFLAGS)"
 LIBTRACEEVENT_FLAGS += plugin_dir=$(plugindir_SQ)
 
-$(LIBTRACEEVENT): $(TE_SOURCES) $(OUTPUT)PERF-CFLAGS
+$(LIBTRACEEVENT): $(TE_SOURCES)
 	$(QUIET_SUBDIR0)$(TRACE_EVENT_DIR) $(LIBTRACEEVENT_FLAGS) libtraceevent.a plugins
 
 $(LIBTRACEEVENT)-clean:
@@ -444,17 +444,6 @@ cscope:
 	$(QUIET_GEN)$(RM) cscope*; \
 	$(FIND) $(TAG_FOLDERS) -name '*.[hcS]' -print | xargs cscope -b $(TAG_FILES)
 
-### Detect prefix changes
-TRACK_CFLAGS = $(subst ','\'',$(CFLAGS)):\
-             $(bindir_SQ):$(perfexecdir_SQ):$(template_dir_SQ):$(prefix_SQ):$(plugindir_SQ)
-
-$(OUTPUT)PERF-CFLAGS: .FORCE-PERF-CFLAGS
-	@FLAGS='$(TRACK_CFLAGS)'; \
-	    if test x"$$FLAGS" != x"`cat $(OUTPUT)PERF-CFLAGS 2>/dev/null`" ; then \
-		echo 1>&2 "  FLAGS:   * new build flags or prefix"; \
-		echo "$$FLAGS" >$(OUTPUT)PERF-CFLAGS; \
-            fi
-
 ### Testing rules
 
 # GNU make supports exporting all variables by "export" without parameters.
@@ -544,7 +533,7 @@ clean: $(LIBTRACEEVENT)-clean $(LIBAPIKFS)-clean config-clean
 	@find . -name '*.o' -delete -o -name '\.*.cmd' -delete -o -name '\.*.d' -delete
 	@$(RM) .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)PERF-CFLAGS $(OUTPUT)PERF-FEATURES $(OUTPUT)util/*-bison* $(OUTPUT)util/*-flex*
+	$(call QUIET_CLEAN, core-gen)   $(RM)  *.spec *.pyc *.pyo */*.pyc */*.pyo $(OUTPUT)common-cmds.h TAGS tags cscope* $(OUTPUT)PERF-VERSION-FILE $(OUTPUT)PERF-FEATURES $(OUTPUT)util/*-bison* $(OUTPUT)util/*-flex*
 	$(QUIET_SUBDIR0)Documentation $(QUIET_SUBDIR1) clean
 	$(python-clean)
 
@@ -562,5 +551,5 @@ FORCE:
 
 .PHONY: all install clean config-clean strip install-gtk
 .PHONY: shell_compatibility_test please_set_SHELL_PATH_to_a_more_modern_shell
-.PHONY: $(GIT-HEAD-PHONY) TAGS tags cscope .FORCE-PERF-CFLAGS FORCE single_dep
+.PHONY: $(GIT-HEAD-PHONY) TAGS tags cscope FORCE single_dep