code_size_compare: direct error message by logger.error

Signed-off-by: Yanray Wang <yanray.wang@arm.com>
diff --git a/scripts/code_size_compare.py b/scripts/code_size_compare.py
index 0c29c41..53d4e3b 100755
--- a/scripts/code_size_compare.py
+++ b/scripts/code_size_compare.py
@@ -262,16 +262,16 @@
                               "and configuration: {}.\n"
                               .format(self.arch,
                                       self.config))
-            self.logger.info("Please use supported combination of " \
+            self.logger.error("Please use supported combination of " \
                              "architecture and configuration:")
             for comb in CodeSizeBuildInfo.SupportedArchConfig:
-                self.logger.info(comb)
-            self.logger.info("")
-            self.logger.info("For your system, please use:")
+                self.logger.error(comb)
+            self.logger.error("")
+            self.logger.error("For your system, please use:")
             for comb in CodeSizeBuildInfo.SupportedArchConfig:
                 if "default" in comb and self.host_arch not in comb:
                     continue
-                self.logger.info(comb)
+                self.logger.error(comb)
             sys.exit(1)