integrate libosmocore logging into firmware

We do so using our own 'raw' log target to avoid the 4k-on-stack
buffer of libosmocore _output() function.

Change-Id: I7a10b5b2b50bcee0154a1fa3fc43756aec836226
diff --git a/sysmoOCTSIM/main.c b/sysmoOCTSIM/main.c
index 80b52dc..01ea0a8 100644
--- a/sysmoOCTSIM/main.c
+++ b/sysmoOCTSIM/main.c
@@ -946,11 +946,12 @@
 }
 
 extern void testmode_init(void);
+extern void libosmo_emb_init(void);
 
 #include "talloc.h"
+#include "logging.h"
 #include <osmocom/core/msgb.h>
 void *g_tall_ctx;
-void *g_msgb_ctx;
 
 DEFUN(_talloc_report, cmd_talloc_report, "talloc-report", "Generate a talloc report")
 {
@@ -1039,8 +1040,10 @@
 	talloc_enable_null_tracking();
 	g_tall_ctx = talloc_named_const(NULL, 0, "global");
 	printf("g_tall_ctx=%p\r\n", g_tall_ctx);
-	g_msgb_ctx = talloc_pool(g_tall_ctx, 20480);
-	talloc_set_memlimit(g_msgb_ctx, 20480);
+
+	libosmo_emb_init();
+
+	LOGP(DUSB, LOGL_ERROR, "foobar usb\n");
 
 	command_print_prompt();
 	while (true) { // main loop