lightnvm: pblk: fix TRACE_INCLUDE_PATH

As the comment block in include/trace/define_trace.h says,
TRACE_INCLUDE_PATH should be a relative path to the define_trace.h

../../drivers/lightnvm is the correct relative path.

../../../drivers/lightnvm is working by coincidence because the top
Makefile adds -I$(srctree)/arch/$(SRCARCH)/include as a header
search path, but we should not rely on it.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Hans Holmberg <hans.holmberg@cnexlabs.com>
Signed-off-by: Matias Bjørling <mb@lightnvm.io>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

drivers/lightnvm/pblk-trace.h

@@ -139,7 +139,7 @@ TRACE_EVENT(pblk_state,
 /* This part must be outside protection */
 
 #undef TRACE_INCLUDE_PATH
-#define TRACE_INCLUDE_PATH ../../../drivers/lightnvm
+#define TRACE_INCLUDE_PATH ../../drivers/lightnvm
 #undef TRACE_INCLUDE_FILE
 #define TRACE_INCLUDE_FILE pblk-trace
 #include <trace/define_trace.h>