perf tools: Introduce tools/lib/lk library

This introduces the tools/lib/lk library, that will gradually have the
routines that now are used in tools/perf/ and other tools and that can
be shared.

Start by carving out debugfs routines for general use.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/1361374353-30385-5-git-send-email-bp@alien8.de
[ committer note: Add tools/lib/lk/ to perf's MANIFEST so that its tarballs continue to build ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/Makefile b/tools/Makefile
index 798fa0e..623b1cd 100644
--- a/tools/Makefile
+++ b/tools/Makefile
@@ -33,7 +33,13 @@
 cpupower: FORCE
 	$(call descend,power/$@)
 
-firewire lguest perf usb virtio vm: FORCE
+firewire guest usb virtio vm: FORCE
+	$(call descend,$@)
+
+liblk: FORCE
+	$(call descend,lib/lk)
+
+perf: liblk FORCE
 	$(call descend,$@)
 
 selftests: FORCE
@@ -61,7 +67,13 @@
 cpupower_clean:
 	$(call descend,power/cpupower,clean)
 
-firewire_clean lguest_clean perf_clean usb_clean virtio_clean vm_clean:
+firewire_clean lguest_clean usb_clean virtio_clean vm_clean:
+	$(call descend,$(@:_clean=),clean)
+
+liblk_clean:
+	$(call descend,lib/lk,clean)
+
+perf_clean: liblk_clean
 	$(call descend,$(@:_clean=),clean)
 
 selftests_clean: