Issue #753 - Applied proposed enhancement.

Author: mluis1

src/radio/sx1272/sx1272.c

@@ -750,6 +750,7 @@ void SX1272SetSleep( void )
 {
     TimerStop( &RxTimeoutTimer );
     TimerStop( &TxTimeoutTimer );
+    TimerStop( &RxTimeoutSyncWord );
 
     SX1272SetOpMode( RF_OPMODE_SLEEP );
 
@@ -763,6 +764,7 @@ void SX1272SetStby( void )
 {
     TimerStop( &RxTimeoutTimer );
     TimerStop( &TxTimeoutTimer );
+    TimerStop( &RxTimeoutSyncWord );
 
     SX1272SetOpMode( RF_OPMODE_STANDBY );
     SX1272.Settings.State = RF_IDLE;

src/radio/sx1276/sx1276.c

@@ -857,6 +857,7 @@ void SX1276SetSleep( void )
 {
     TimerStop( &RxTimeoutTimer );
     TimerStop( &TxTimeoutTimer );
+    TimerStop( &RxTimeoutSyncWord );
 
     SX1276SetOpMode( RF_OPMODE_SLEEP );
 
@@ -870,6 +871,7 @@ void SX1276SetStby( void )
 {
     TimerStop( &RxTimeoutTimer );
     TimerStop( &TxTimeoutTimer );
+    TimerStop( &RxTimeoutSyncWord );
 
     SX1276SetOpMode( RF_OPMODE_STANDBY );
     SX1276.Settings.State = RF_IDLE;