build: add BOOST_CPPFLAGS display for configure

configure.ac

@@ -943,21 +943,22 @@ esac
 
 echo 
 echo "Options used to compile and link:"
-echo "  with wallet   = $enable_wallet"
-echo "  with proton   = $use_proton"
-echo "  with zmq      = $use_zmq"
-echo "  with test     = $use_tests"
-echo "  debug enabled = $enable_debug"
-echo "  werror        = $enable_werror"
+echo "  with wallet    = $enable_wallet"
+echo "  with proton    = $use_proton"
+echo "  with zmq       = $use_zmq"
+echo "  with test      = $use_tests"
+echo "  debug enabled  = $enable_debug"
+echo "  werror         = $enable_werror"
 echo 
-echo "  target os     = $TARGET_OS"
-echo "  build os      = $BUILD_OS"
+echo "  target os      = $TARGET_OS"
+echo "  build os       = $BUILD_OS"
 echo
-echo "  CC            = $CC"
-echo "  CFLAGS        = $CFLAGS"
-echo "  CPPFLAGS      = $CPPFLAGS"
-echo "  CXX           = $CXX"
-echo "  CXXFLAGS      = $CXXFLAGS"
-echo "  LDFLAGS       = $LDFLAGS"
-echo "  ARFLAGS       = $ARFLAGS"
+echo "  CC             = $CC"
+echo "  CFLAGS         = $CFLAGS"
+echo "  CPPFLAGS       = $CPPFLAGS"
+echo "  CXX            = $CXX"
+echo "  CXXFLAGS       = $CXXFLAGS"
+echo "  BOOST_CPPFLAGS = $BOOST_CPPFLAGS"
+echo "  LDFLAGS        = $LDFLAGS"
+echo "  ARFLAGS        = $ARFLAGS"
 echo