Add STDP code generation for SpiNNaker target

[clinssen]

Replaces #1225.

NOTE: for now, manually remove the checks in /home/spinnaker/source/sPyNNaker/neural_modelling/makefiles/synapse_only/synapse_build.mk on lines 99-104.

[clinssen]

TODO: make changes to upstream SpyNNaker code unnecessary.

diff --git a/neural_modelling/makefiles/synapse_only/synapse_build.mk b/neural_modelling/makefiles/synapse_only/synapse_build.mk
index b6bfaffa29..004250ecff 100644
--- a/neural_modelling/makefiles/synapse_only/synapse_build.mk
+++ b/neural_modelling/makefiles/synapse_only/synapse_build.mk
@@ -96,12 +96,6 @@ else
     ifneq ($(SYNAPSE_DYNAMICS), $(SYNAPSE_DYNAMICS_STATIC))
         STDP_ENABLED = 1
 
-        ifndef TIMING_DEPENDENCE_H
-            $(error TIMING_DEPENDENCE_H is not set which is required when SYNAPSE_DYNAMICS ($(SYNAPSE_DYNAMICS_C)) != $(SYNAPSE_DYNAMICS_STATIC))
-        endif
-        ifndef WEIGHT_DEPENDENCE_H
-            $(error WEIGHT_DEPENDENCE_H is not set which is required when SYNAPSE_DYNAMICS ($(SYNAPSE_DYNAMICS_C)) != $(SYNAPSE_DYNAMICS_STATIC))
-        endif
     endif
 endif
 
@@ -205,8 +199,10 @@ endif
 
 #STDP Build rules If and only if STDP used
 ifeq ($(STDP_ENABLED), 1)
-    STDP_INCLUDES:= -include $(WEIGHT_DEPENDENCE_H) -include $(TIMING_DEPENDENCE_H)
-    STDP_COMPILE = $(CC) -DLOG_LEVEL=$(PLASTIC_DEBUG) $(CFLAGS) -DSTDP_ENABLED=$(STDP_ENABLED) -DSYNGEN_ENABLED=$(SYNGEN_ENABLED) $(STDP_INCLUDES)
+    #STDP_INCLUDES:= -include $(WEIGHT_DEPENDENCE_H) -include $(TIMING_DEPENDENCE_H)
+    #STDP_INCLUDES:= -include $(WEIGHT_DEPENDENCE_H) -include $(TIMING_DEPENDENCE_H)
+    #STDP_COMPILE = $(CC) -DLOG_LEVEL=$(PLASTIC_DEBUG) $(CFLAGS) -DSTDP_ENABLED=$(STDP_ENABLED) -DSYNGEN_ENABLED=$(SYNGEN_ENABLED) $(STDP_INCLUDES)
+    STDP_COMPILE = $(CC) -DLOG_LEVEL=$(PLASTIC_DEBUG) $(CFLAGS) -DSTDP_ENABLED=$(STDP_ENABLED) -DSYNGEN_ENABLED=$(SYNGEN_ENABLED)
 
     $(SYNAPSE_DYNAMICS_O): $(SYNAPSE_DYNAMICS_C)
        # SYNAPSE_DYNAMICS_O stdp
diff --git a/spynnaker/pyNN/extra_algorithms/spynnaker_neuron_network_specification_report.py b/spynnaker/pyNN/extra_algorithms/spynnaker_neuron_network_specification_report.py
index 9dde48cf80..b65d807513 100644
--- a/spynnaker/pyNN/extra_algorithms/spynnaker_neuron_network_specification_report.py
+++ b/spynnaker/pyNN/extra_algorithms/spynnaker_neuron_network_specification_report.py
@@ -31,7 +31,7 @@ _RE = TypeVar("_RE", bound=RuntimeError)
 
 CUTOFF = 100
 _GRAPH_TITLE = "The graph of the network in graphical form"
-_GRAPH_FORMAT = "png"
+_GRAPH_FORMAT = "svg"
 
 
 def _get_diagram(label: str) -> Tuple[gv.Digraph, Type[gv.ExecutableNotFound]]: