CCFLAGS is used by gcc and g++ compiler. So CFLAGS should be used for gcc to avoid passing gcc flags to g++.
This requires TFM package support to run in the secure side, while the RTT running in non-secure. Change-Id: Ic749f92937fc99e6e29ba4a1be66cb7819670f2c Signed-off-by: Karl Zhang <karl.zhang@arm.com>