CI: Migrate support to MbedTLS v2.24.0

This patch migrates the mbedcrypto dependency for TF-A
to mbedTLS repo v2.24.0 which is the latest release tag.
The relevant files are updated to reflect the use of new
version.

Signed-off-by: Alexei Fedorov <Alexei.Fedorov@arm.com>
Change-Id: Id7df567b586c31d74978b3ec8899e15905987e24
diff --git a/utils.sh b/utils.sh
index 2464760..87129fa 100644
--- a/utils.sh
+++ b/utils.sh
@@ -318,10 +318,10 @@
 linaro_release="${linaro_release:-$linaro_1906_release}"
 
 # mbedTLS archive public hosting available at github.com
-mbedtls_archive="${mbedtls_archive:-https://github.com/ARMmbed/mbedtls/archive/mbedtls-2.18.0.tar.gz}"
-# The tar file contains mbedtls-mbedtls-2.18.0 repo which holds the necessary
+mbedtls_archive="${mbedtls_archive:-https://github.com/ARMmbed/mbedtls/archive/mbedtls-2.24.0.tar.gz}"
+# The tar file contains mbedtls-mbedtls-2.24.0 repo which holds the necessary
 # source files of mbedTLS project
-mbedtls_repo_name="${mbedtls_repo_name:-mbedtls-mbedtls-2.18.0}"
+mbedtls_repo_name="${mbedtls_repo_name:-mbedtls-mbedtls-2.24.0}"
 
 coverity_path="${coverity_path:-${nfs_volume}/tools/coverity/static-analysis/2019.09}"
 coverity_default_checkers=(