build: avoid the use of top_ and abs_ dir paths

Using them has the side effect of confusing the dependency-tracking logic.

src/Makefile.am

@@ -1,5 +1,5 @@
 AM_CPPFLAGS =  $(INCLUDES) \
-  -I$(top_builddir)/src/obj \
+  -I$(builddir)/obj \
   $(BDB_CPPFLAGS) \
   $(BOOST_CPPFLAGS) $(BOOST_INCLUDES)
 AM_CPPFLAGS += $(LEVELDB_CPPFLAGS)
@@ -8,10 +8,10 @@ AM_LDFLAGS = $(PTHREAD_CFLAGS)
 AM_CPPFLAGS += -I$(builddir)
 
 if EMBEDDED_LEVELDB
-LEVELDB_CPPFLAGS += -I$(top_srcdir)/src/leveldb/include
-LEVELDB_CPPFLAGS += -I$(top_srcdir)/src/leveldb/helpers/memenv
-LIBLEVELDB += $(top_builddir)/src/leveldb/libleveldb.a
-LIBMEMENV  += $(top_builddir)/src/leveldb/libmemenv.a
+LEVELDB_CPPFLAGS += -I$(srcdir)/leveldb/include
+LEVELDB_CPPFLAGS += -I$(srcdir)/leveldb/helpers/memenv
+LIBLEVELDB += $(builddir)/leveldb/libleveldb.a
+LIBMEMENV  += $(builddir)/leveldb/libmemenv.a
 
 # NOTE: This dependency is not strictly necessary, but without it make may try to build both in parallel, which breaks the LevelDB build system in a race
 $(LIBLEVELDB): $(LIBMEMENV)
@@ -101,7 +101,7 @@ JSON_H = \
   json/json_spirit_writer_template.h
 
 obj/build.h: FORCE
-	@$(MKDIR_P) $(abs_top_builddir)/src/obj
+	@$(MKDIR_P) $(builddir)/obj
 	@$(top_srcdir)/share/genbuild.sh $(abs_top_builddir)/src/obj/build.h \
 	  $(abs_top_srcdir)
 version.o: obj/build.h
@@ -164,7 +164,7 @@ libbitcoin_cli_a_SOURCES = \
   rpcclient.cpp \
   $(BITCOIN_CORE_H)
 
-nodist_libbitcoin_common_a_SOURCES = $(top_srcdir)/src/obj/build.h
+nodist_libbitcoin_common_a_SOURCES = $(srcdir)/obj/build.h
 #
 
 # bitcoind binary #