fix warnings from "gcc -Wconversion" (#1271)

fix warnings from "gcc -Wconversion"

Signed-off-by: Florian La Roche <Florian.LaRoche@gmail.com>
diff --git a/portable/Common/mpu_wrappers_v2.c b/portable/Common/mpu_wrappers_v2.c
index e92aca0..9f9fa43 100644
--- a/portable/Common/mpu_wrappers_v2.c
+++ b/portable/Common/mpu_wrappers_v2.c
@@ -1059,8 +1059,8 @@
                                                   configRUN_TIME_COUNTER_TYPE * pulTotalRunTime ) /* PRIVILEGED_FUNCTION */
         {
             UBaseType_t uxReturn = 0;
-            UBaseType_t xIsTaskStatusArrayWriteable = pdFALSE;
-            UBaseType_t xIsTotalRunTimeWriteable = pdFALSE;
+            BaseType_t xIsTaskStatusArrayWriteable = pdFALSE;
+            BaseType_t xIsTotalRunTimeWriteable = pdFALSE;
             uint32_t ulArraySize = ( uint32_t ) uxArraySize;
             uint32_t ulTaskStatusSize = ( uint32_t ) sizeof( TaskStatus_t );