tools build: Make the fixdep helper part of the build process

Making the fixdep helper to be invoked within dep-cmd.

Each user of the build framework needs to make sure fixdep exists before
executing the build itself.

If the build doesn't find fixdep, it falls back to the old style
dependency tracking.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1443004442-32660-6-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/build/Makefile.build b/tools/build/Makefile.build
index 0c5f485..4a96473 100644
--- a/tools/build/Makefile.build
+++ b/tools/build/Makefile.build
@@ -21,6 +21,13 @@
 
 build-dir := $(srctree)/tools/build
 
+# Define $(fixdep) for dep-cmd function
+ifeq ($(OUTPUT),)
+  fixdep := $(build-dir)/fixdep
+else
+  fixdep := $(OUTPUT)/fixdep
+endif
+
 # Generic definitions
 include $(build-dir)/Build.include