Fix compilation errors when building sign_with_k test function

Signed-off-by: Andrzej Kurek <andrzej.kurek@arm.com>
diff --git a/scripts/baremetal.sh b/scripts/baremetal.sh
index 53ccedb..e2c0338 100755
--- a/scripts/baremetal.sh
+++ b/scripts/baremetal.sh
@@ -97,7 +97,7 @@
     if [ $check -ne 0 ]; then
         CFLAGS_BAREMETAL="$CFLAGS_BAREMETAL -Werror"
     fi
-    CFLAGS="$CFLAGS_BAREMETAL $CFLAGS_CONFIG"
+    CFLAGS="$CFLAGS_BAREMETAL $CFLAGS_CONFIG -DENABLE_TESTS"
 
     echo "GCC version: $gcc_ver"
     echo "Flags: $CFLAGS_BAREMETAL"
@@ -132,7 +132,7 @@
     fi
 
     CFLAGS_BAREMETAL="$OPTIM_CFLAGS_ARMC5 --thumb --cpu Cortex-m0plus"
-    CFLAGS="$CFLAGS_BAREMETAL $CFLAGS_CONFIG"
+    CFLAGS="$CFLAGS_BAREMETAL $CFLAGS_CONFIG -DENABLE_TESTS"
     WARNING_CFLAGS="--strict --c99"
 
     if [ $check -ne 0 ]; then
@@ -175,7 +175,7 @@
     if [ $check -ne 0 ]; then
         CFLAGS_BAREMETAL="$CFLAGS_BAREMETAL -Werror"
     fi
-    CFLAGS="$CFLAGS_BAREMETAL $CFLAGS_CONFIG"
+    CFLAGS="$CFLAGS_BAREMETAL $CFLAGS_CONFIG -DENABLE_TESTS"
 
     echo "ARMC6 version: $armc6_ver"
     echo "Flags: $CFLAGS_BAREMETAL"
@@ -204,7 +204,7 @@
     echo "Cleanup..."
     make clean
 
-    CFLAGS="$BASE_CFLAGS $CFLAGS_CONFIG $CFLAGS_USER_CONFIG"
+    CFLAGS="$BASE_CFLAGS $CFLAGS_CONFIG $CFLAGS_USER_CONFIG -DENABLE_TESTS"
     if [ "$build_only" -eq 1 ]; then
         CFLAGS="$CFLAGS -Werror"
     fi