Replaced const define with hardcoded bus size of 16

libraries/mbed/common/BusIn.cpp

@@ -73,7 +73,7 @@ BusIn::operator int() {
 }
 
 DigitalIn& BusIn::operator[] (int index) {
-    MBED_ASSERT(index < 0 || index >= MBED_BUS_SIZE);
+    MBED_ASSERT(index < 0 || index >= 16);
     MBED_ASSERT(_pin[index]);
     if (index >= 16 || _pin[index] == NULL) {
         return din_dummy;

libraries/mbed/common/BusInOut.cpp

@@ -103,7 +103,7 @@ BusInOut& BusInOut::operator= (BusInOut& rhs) {
 }
 
 DigitalInOut& BusInOut::operator[] (int index) {
-    MBED_ASSERT(index < 0 || index >= MBED_BUS_SIZE);
+    MBED_ASSERT(index < 0 || index >= 16);
     MBED_ASSERT(_pin[index]);
     if (index >= 16 || _pin[index] == NULL) {
         return dinout_dummy;

libraries/mbed/common/BusOut.cpp

@@ -79,7 +79,7 @@ BusOut& BusOut::operator= (BusOut& rhs) {
 }
 
 DigitalOut& BusOut::operator[] (int index) {
-    MBED_ASSERT(index < 0 || index >= MBED_BUS_SIZE);
+    MBED_ASSERT(index < 0 || index >= 16);
     MBED_ASSERT(_pin[index]);
     if (index >= 16 || _pin[index] == NULL) {
         return dout_dummy;