Use global PCU's talloc context for all talloc calls

This allows to track memory leaks of all memory that is allocated by
talloc. Especially bitvector allocations is tracked now.
diff --git a/src/pcu_main.cpp b/src/pcu_main.cpp
index 142c9f9..a9e224f 100644
--- a/src/pcu_main.cpp
+++ b/src/pcu_main.cpp
@@ -39,6 +39,7 @@
 static const char *config_file = "osmo-pcu.cfg";
 extern struct vty_app_info pcu_vty_info;
 void *tall_pcu_ctx;
+extern void *bv_tall_ctx;
 static int quit = 0;
 
 #ifdef DEBUG_DIAGRAM
@@ -140,6 +141,7 @@
 	tall_pcu_ctx = talloc_named_const(NULL, 1, "Osmo-PCU context");
 	if (!tall_pcu_ctx)
 		return -ENOMEM;
+	bv_tall_ctx = tall_pcu_ctx;
 
 	bts = gprs_rlcmac_bts = talloc_zero(tall_pcu_ctx,
 						struct gprs_rlcmac_bts);
diff --git a/src/sysmo_l1_if.c b/src/sysmo_l1_if.c
index 7cb1d17..68881bf 100644
--- a/src/sysmo_l1_if.c
+++ b/src/sysmo_l1_if.c
@@ -14,6 +14,8 @@
 #include <gprs_debug.h>
 #include <pcu_l1_if.h>
 
+extern void *tall_pcu_ctx;
+
 uint32_t l1if_ts_to_hLayer2(uint8_t trx, uint8_t ts)
 {
 	return (ts << 16) | (trx << 24);
@@ -320,7 +322,7 @@
 	struct femtol1_hdl *fl1h;
 	int rc;
 
-	fl1h = talloc_zero(priv, struct femtol1_hdl);
+	fl1h = talloc_zero(tall_pcu_ctx, struct femtol1_hdl);
 	if (!fl1h)
 		return NULL;