Watchdog: remove config value for timeout, set it dynamically

Use start method to set timeout

Author: 0xc0170

UNITTESTS/drivers/Watchdog/test_watchdog.cpp

@@ -63,6 +63,6 @@ TEST_F(TestWatchdog, test_watchdog_get_max_timeout)
 
 TEST_F(TestWatchdog, test_watchdog_get_timeout)
 {
-    EXPECT_EQ(500, Watchdog::get_instance().get_timeout());
+    EXPECT_EQ(Watchdog::watchdog_timeout, Watchdog::get_instance().get_timeout());
 }
 

UNITTESTS/drivers/Watchdog/unittest.cmake

@@ -24,5 +24,5 @@ set(unittest-test-sources
 )
 
 # defines
-set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DDEVICE_WATCHDOG -DMBED_WDOG_ASSERT=1 -DMBED_CONF_TARGET_WATCHDOG_TIMEOUT=500")
-set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DDEVICE_WATCHDOG -DMBED_WDOG_ASSERT=1 -DMBED_CONF_TARGET_WATCHDOG_TIMEOUT=500")
+set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -DDEVICE_WATCHDOG -DMBED_WDOG_ASSERT=1")
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -DDEVICE_WATCHDOG -DMBED_WDOG_ASSERT=1")

drivers/Watchdog.h

@@ -51,7 +51,7 @@ namespace mbed {
  */
 class Watchdog : private NonCopyable<Watchdog>  {
 public:
-    static const uint32_t watchdog_timeout = MBED_CONF_TARGET_WATCHDOG_TIMEOUT;
+    static const uint32_t watchdog_timeout = 800;
 
     /** As Watchdog might not stop ever, there is just one instance - we use single instance.
       * This ensures we keep Watchdog alive. To operate watchdog, use start/stop methods.

targets/targets.json

@@ -47,10 +47,6 @@
             "tickless-from-us-ticker": {
                 "help": "Run tickless from the microsecond ticker rather than the low power ticker. Running tickless off of the microsecond ticker improves interrupt latency on targets which use lpticker_delay_ticks",
                 "value": false
-            },
-            "watchdog-timeout": {
-                "help": "Define the timeout in ms to do HW kick",
-                "value": "800"
             }
         }
     },