These do not link directly against Mbed TLS so need their own
propagation of the custom config values through CMake.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
MBEDTLS_TARGET_PREFIX is prepended to the CMake targets for Mbed TLS
except for targets in 3rdparty. Change this so that 3rdparty targets use
the prefix as well.
This allows multiple copies of Mbed TLS to be used in the same CMake
tree when using code in the 3rdparty directory.
Signed-off-by: David Horstmann <david.horstmann@arm.com>
