Segfault at start up when loading a patch and getting messages at the same time.

[loki42]

When sending messages to Ingen at start up while loading a patch Ingen segfaults. This is with latest code / dependencies.
If you load the patch first, then wait for send messages after everything is done, no crash, if you send it during start up crash. Ingen shouldn't accept connections until it's done loading the initial preset, unless there's a proper fix for this.

_:b150
	a patch:Set ;
	patch:subject <ingen:/main/amp_nam2/output_level> ;
	patch:property midi:binding ;
	patch:value [
		a midi:Controller ;
		midi:controllerNumber "35"^^xsd:int
	] .

_:b152
	a patch:Patch ;
	patch:subject <ingen:/main/amp_nam1/input_level> ;
	patch:remove [
		midi:binding patch:wildcard
	] ;
	patch:add [] .

Thread 3 "ingen" received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xfffff704f180 (LWP 37272)]
ingen::server::ClientUpdate::put_port (this=0xffffec00a9f8, port=0x70) at ../src/server/ClientUpdate.cpp:55
55		const URIs& uris = port->bufs().uris();
(gdb) bt
#0  ingen::server::ClientUpdate::put_port (this=0xffffec00a9f8, port=0x70) at ../src/server/ClientUpdate.cpp:55
#1  0x0000fffff78c79d8 in ingen::server::ClientUpdate::put_graph (this=this@entry=0xffffec00a9f8, graph=0xfffff0261010)
    at ../src/server/ClientUpdate.cpp:100
#2  0x0000fffff78ab658 in ingen::server::events::Get::pre_process (this=0xffffec00a8d0) at ../src/server/events/Get.cpp:72
#3  0x0000fffff78f3d68 in ingen::server::PreProcessor::run (this=0xaaaaaac26500) at ../src/server/PreProcessor.cpp:221
#4  0x0000fffff7d8e9dc in ?? () from /lib/aarch64-linux-gnu/libstdc++.so.6
#5  0x0000fffff7b4ee18 in start_thread (arg=0xffffffffea87) at ./nptl/pthread_create.c:442
#6  0x0000fffff7bb7e9c in thread_start () at ../sysdeps/unix/sysv/linux/aarch64/clone.S:79