firmware: qcom: tzmem: simplify returning pointer without cleanup

Use 'return_ptr' helper for returning a pointer without cleanup for
shorter code.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20240703083046.95811-1-krzysztof.kozlowski@linaro.org


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