MLECO-1910: Fix for CPU counter difference

Fixed the CPU counter being truncated by the diff function's return type.

Change-Id: I9417dbc9da357f8593b67c3a94620ac6e62eddbf
diff --git a/source/application/hal/platforms/bare-metal/timer/baremetal_timer.c b/source/application/hal/platforms/bare-metal/timer/baremetal_timer.c
index 64f2376..cd17a60 100644
--- a/source/application/hal/platforms/bare-metal/timer/baremetal_timer.c
+++ b/source/application/hal/platforms/bare-metal/timer/baremetal_timer.c
@@ -146,7 +146,7 @@
  * @return  CPU cycle difference between given time counters expressed
  *          as unsigned 32 bit integer.
  **/
-static uint32_t bm_get_cpu_cycles_diff(time_counter *st, time_counter *end);
+static uint64_t bm_get_cpu_cycles_diff(time_counter *st, time_counter *end);
 
 /**
  * @brief       Initialiser for bare metal timer.
@@ -335,7 +335,7 @@
     return bm_get_time_counter();
 }
 
-static uint32_t bm_get_cpu_cycles_diff(time_counter *st, time_counter *end)
+static uint64_t bm_get_cpu_cycles_diff(time_counter *st, time_counter *end)
 {
     return get_cycle_count_diff(&(st->counter), &(end->counter));
 }