libperf: Move to tools/lib/perf

Move libperf from its current location under tools/perf to a separate
directory under tools/lib/.

Also change various paths (mainly includes) to reflect the libperf move
to a separate directory and add a new directory under MANIFEST.

Signed-off-by: Jiri Olsa <[e-mail]>
Tested-by: Arnaldo Carvalho de Melo <[e-mail]>
Cc: Alexander Shishkin <[e-mail]>
Cc: Michael Petlan <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Link: http://lore.kernel.org/lkml/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/MANIFEST

···
 tools/lib/api
 tools/lib/bpf
 tools/lib/subcmd
+tools/lib/perf
 tools/lib/argv_split.c
 tools/lib/ctype.c
 tools/lib/hweight.c

tools/perf/Makefile.config

···
   endif
 endif
 
-INC_FLAGS += -I$(src-perf)/lib/include
+INC_FLAGS += -I$(srctree)/tools/lib/perf/include
 INC_FLAGS += -I$(src-perf)/util/include
 INC_FLAGS += -I$(src-perf)/arch/$(SRCARCH)/include
 INC_FLAGS += -I$(srctree)/tools/include/

tools/perf/Makefile.perf

···
 TRACE_EVENT_DIR = $(srctree)/tools/lib/traceevent/
 BPF_DIR         = $(srctree)/tools/lib/bpf/
 SUBCMD_DIR      = $(srctree)/tools/lib/subcmd/
-LIBPERF_DIR     = $(srctree)/tools/perf/lib/
+LIBPERF_DIR     = $(srctree)/tools/lib/perf/
 
 # Set FEATURE_TESTS to 'all' so all possible feature checkers are executed.
 # Without this setting the output feature dump file misses some features, for

tools/perf/lib/Makefile tools/lib/perf/Makefile

···
 endif
 
 INCLUDES = \
--I$(srctree)/tools/perf/lib/include \
+-I$(srctree)/tools/lib/perf/include \
 -I$(srctree)/tools/lib/ \
 -I$(srctree)/tools/include \
 -I$(srctree)/tools/arch/$(SRCARCH)/include/ \

tools/perf/lib/tests/Makefile tools/lib/perf/tests/Makefile

···
 
 include $(srctree)/tools/scripts/Makefile.include
 
-INCLUDE = -I$(srctree)/tools/perf/lib/include -I$(srctree)/tools/include -I$(srctree)/tools/lib
+INCLUDE = -I$(srctree)/tools/lib/perf/include -I$(srctree)/tools/include -I$(srctree)/tools/lib
 
 $(TESTS_A): FORCE
 	$(QUIET_LINK)$(CC) $(INCLUDE) $(CFLAGS) -o $@ $(subst -a,.c,$@) ../libperf.a $(LIBAPI)