firmware: qcom: qseecom: remove unused functions

qseecom_scm_dev(), qseecom_dma_alloc() and qseecom_dma_free() are no
longer used following the conversion to using tzmem. Remove them.

Fixes: 6612103e ("firmware: qcom: qseecom: convert to using the TZ allocator")
Reviewed-by: Andrew Halaney <ahalaney@redhat.com>
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20240731-tzmem-efivars-fix-v2-2-f0e84071ec07@linaro.org


Signed-off-by: Bjorn Andersson <andersson@kernel.org>