Add time conversion macros (#866)

This commit updates the following time conversion macros:

- pdMS_TO_TICKS: Added cast to "uint64_t" to prevent overflow
- pdTICKS_TO_MS: Added macro to convert ticks to milliseconds

Co-authored-by: Gaurav-Aggarwal-AWS <33462878+aggarg@users.noreply.github.com>
Co-authored-by: Rahul Kar <118818625+kar-rahul-aws@users.noreply.github.com>

include/projdefs.h

@@ -39,7 +39,14 @@ typedef void (* TaskFunction_t)( void * );
  * overridden by a macro of the same name defined in FreeRTOSConfig.h in case the
  * definition here is not suitable for your application. */
 #ifndef pdMS_TO_TICKS
-    #define pdMS_TO_TICKS( xTimeInMs )    ( ( TickType_t ) ( ( ( TickType_t ) ( xTimeInMs ) * ( TickType_t ) configTICK_RATE_HZ ) / ( TickType_t ) 1000U ) )
+    #define pdMS_TO_TICKS( xTimeInMs )    ( ( TickType_t ) ( ( ( uint64_t ) ( xTimeInMs ) * ( uint64_t ) configTICK_RATE_HZ ) / ( uint64_t ) 1000U ) )
+#endif
+
+/* Converts a time in ticks to a time in milliseconds.  This macro can be
+ * overridden by a macro of the same name defined in FreeRTOSConfig.h in case the
+ * definition here is not suitable for your application. */
+#ifndef pdTICKS_TO_MS
+    #define pdTICKS_TO_MS( xTimeInTicks )    ( ( TickType_t ) ( ( ( uint64_t ) ( xTimeInTicks ) * ( uint64_t ) 1000U ) / ( uint64_t ) configTICK_RATE_HZ ) )
 #endif
 
 #define pdFALSE                                  ( ( BaseType_t ) 0 )