Adding correction to documentation
Adding correction to documentation

As picked up in review, this commit
modifies the documentation by removing some
wording that is now superfluous given the
removal of the mode parameter.

Signed-off-by: Thomas Daubney <5b910c8e7c225fd62319de5b44eecef1f6356fe1@arm.com>

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