build(mbedtls): add deprecation notice

Add a deprecation notice for building TF-A with mbedtls-2.x
This was notified earlier in TF-A mailing list:

https://lists.trustedfirmware.org/archives/list/tf-a@lists.trustedfirmware.org/message/YDPOPASMGEQBCOI5TKUSD3V3J75NAT7A/

We will be removing support to build TF-A with mbedtls-2.x after
TF-A 2.10 release.

Change-Id: I669b423ee9af9f5c5255fce370413fffaf38e8eb
Signed-off-by: Govindraj Raja <govindraj.raja@arm.com>

docs/about/release-information.rst

@@ -81,6 +81,8 @@ after which it will be removed.
 |                                | Date        | after   |                                                         |
 |                                |             | Release |                                                         |
 +================================+=============+=========+=========================================================+
+| Mbedtls-2.x                    |     2.10    |   2.10  | Support for TF-A builds with Mbedtls-2.x will be removed|
++--------------------------------+-------------+---------+---------------------------------------------------------+
 | STM32MP15_OPTEE_RSV_SHM        |     2.10    |   3.0   | OP-TEE manages its own memory on STM32MP15              |
 +--------------------------------+-------------+---------+---------------------------------------------------------+
 

drivers/auth/mbedtls/mbedtls_common.mk

@@ -21,7 +21,8 @@ $(info MBEDTLS_VERSION_MAJOR is [${MBEDTLS_MAJOR}] MBEDTLS_VERSION_MINOR is [${M
 
 # Specify mbed TLS configuration file
 ifeq (${MBEDTLS_MAJOR}, 2)
-	MBEDTLS_CONFIG_FILE	?=	"<drivers/auth/mbedtls/mbedtls_config-2.h>"
+        $(info Deprecation Notice: Please migrate to Mbedtls version 3.x (refer to TF-A documentation for the exact version number))
+	MBEDTLS_CONFIG_FILE             ?=	"<drivers/auth/mbedtls/mbedtls_config-2.h>"
 else ifeq (${MBEDTLS_MAJOR}, 3)
 	ifeq (${PSA_CRYPTO},1)
 		MBEDTLS_CONFIG_FILE     ?=      "<drivers/auth/mbedtls/psa_mbedtls_config.h>"