ta/ta.mk: remove useless calls to $(wildcard)
ta/ta.mk: remove useless calls to $(wildcard)

File names passed to $(wildcard) in ta/mk contain no wildcarding
token and they all exist. Therefore, $(wildcard <file>) is always equal
to <file> and $(wildcard) may be omitted.

Signed-off-by: Jerome Forissier <ced78d268b4c9a0a20a59a9feeebd2ad90da03d3@linaro.org>
Reviewed-by: Jens Wiklander <7706914404370d7502c27a0eff493dcf491feb51@linaro.org>

pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os