MLECO-2983: Preliminary support to allow semihosting

Adding basic support to allow applications to build with semihosting
support. Default state is always disabled.

Signed-off-by: Kshitij Sisodia <kshitij.sisodia@arm.com>
Change-Id: I1d34c3a246560aaffcb34eee801e1a87d887d559
diff --git a/source/hal/profiles/bare-metal/bsp/retarget.c b/source/hal/profiles/bare-metal/bsp/retarget.c
index dfef62c..9ed3004 100644
--- a/source/hal/profiles/bare-metal/bsp/retarget.c
+++ b/source/hal/profiles/bare-metal/bsp/retarget.c
@@ -14,6 +14,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+#if !defined(USE_SEMIHOSTING)
 
 #include "uart_stdout.h"
 
@@ -266,3 +267,5 @@
 }
 
 #endif /* #ifndef ferror */
+
+#endif /* !defined(USE_SEMIHOSTING) */