Add missing creation of timer tSMP_CB.smp_rsp_timer_ent

Add missing creation of timer tSMP_CB.smp_rsp_timer_ent so
the timer is not NULL.

Bug: 26611369
Change-Id: I2882d40090599b628ecee777b244376168806776
diff --git a/stack/smp/smp_utils.c b/stack/smp/smp_utils.c
index d9b456f..f9e66a7 100644
--- a/stack/smp/smp_utils.c
+++ b/stack/smp/smp_utils.c
@@ -877,6 +877,7 @@
     memset(p_cb, 0, sizeof(tSMP_CB));
     p_cb->p_callback = p_callback;
     p_cb->trace_level = trace_level;
+    p_cb->smp_rsp_timer_ent = alarm_new("smp.smp_rsp_timer_ent");
 }
 
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