Build: Remove Library Model branch in build system

Library Model is deprecated, so remove library model branch in build
system:
 - TFM_PSA_API/TFM_LIB_MODEL
 - remove tfm_library_config_default.cmake

Signed-off-by: Summer Qin <summer.qin@arm.com>
Change-Id: I644fbdb6041ba07ed35829a412472c7ac467c94d
35 files changed