Bluetooth: controller: split: Increase event start overhead time

Increase the event start overhead time to accommodate for
processing time for dequeueing pipeline in Upper Link Layer.

Signed-off-by: Vinayak Kariappa Chettimada <[email protected]>

Author: cvinayak

subsys/bluetooth/controller/ll_sw/nordic/lll/lll_vendor.h

@@ -8,7 +8,7 @@
 #define EVENT_OVERHEAD_PREEMPT_US     0    /* if <= min, then dynamic preempt */
 #define EVENT_OVERHEAD_PREEMPT_MIN_US 0
 #define EVENT_OVERHEAD_PREEMPT_MAX_US EVENT_OVERHEAD_XTAL_US
-#define EVENT_OVERHEAD_START_US       200
+#define EVENT_OVERHEAD_START_US       300
 /* Worst-case time margin needed after event end-time in the air
  * (done/preempt race margin + power-down/chain delay)
  */