refinfra: update mbedtls version to v3.6.2
With TF-a commit '7dc43344' "update-mbedtls-to-3.6.2" into integration TF-A expects the mbdeTLS library to be at v3.6.2. Update the manifests to meet this requirement.
Signed-off-by: Raghuram Thammiraju raghuram.thammiraju@arm.com Change-Id: Iae6e59430757c3c5799950f3416f4e7ae5f9d8ea