Add a partial plan towards G5
Add a partial plan towards G5

Strategy for dependencies inside libmbecrypto, in particular in the PSA
Crypto core, are outside the scope of the present study.

Note: PR 6065, referenced in a few places, is the one that also
introduces the present commit. It kicks of the work towards G5 in parts
of the code governed by MBEDTLS_USE_PSA_CRYPTO.

Signed-off-by: Manuel Pégourié-Gonnard <4ba0d615aeeda88e422ca8fba28fe2938485facf@arm.com>

ARMmbed/mbedtls,Mbed-TLS/mbedtls,ARMmbed/mbedtls,Mbed-TLS/mbedtls,ARMmbed/mbedtls,ARMmbed/mbedtls,Mbed-TLS/mbedtls,Mbed-TLS/mbedtls