Add Controller task size config defaults

* Fixes issues with some devices where the controller stack overflows

Author: h2zero

cores/nRF5/nimble_config/ext_nimble_config.h

@@ -100,4 +100,8 @@ MYNEWT_VAL_MCU_TARGET__nRF5340_NET
 /* FIX DLE with Nimble core 1.6 */
 #if MYNEWT_VAL_BLE_LL_CFG_FEAT_LE_CODED_PHY
 #define BLE_50_FEATURE_SUPPORT 1
+#endif
+
+#ifndef CONFIG_BT_NIMBLE_LL_TASK_STACK_SIZE
+#define CONFIG_BT_NIMBLE_LL_TASK_STACK_SIZE 512
 #endif

cores/nRF5/nimble_config/nrf51_nimconfig.h

@@ -51,6 +51,10 @@
 #  endif
 #endif
 
+#ifndef CONFIG_BT_NIMBLE_LL_TASK_STACK_SIZE
+#define CONFIG_BT_NIMBLE_LL_TASK_STACK_SIZE 400
+#endif
+
 #ifndef CONFIG_BT_NIMBLE_ATT_PREFERRED_MTU
 #define CONFIG_BT_NIMBLE_ATT_PREFERRED_MTU (23)
 #endif