interconnect: qcom: icc-rpm: Explicitly return 0 at the end of the function

Fix the following smatch error:
drivers/interconnect/qcom/icc-rpm.c:243 qcom_icc_rpm_set() error: uninitialized symbol 'ret'.

Fixes: 32846c4a ("interconnect: qcom: icc-rpm: Set bandwidth on both contexts")
Reviewed-by: Stephan Gerhold <stephan@gerhold.net>
Link: https://lore.kernel.org/r/20230717125534.2455745-1-djakov@kernel.org


Signed-off-by: Georgi Djakov <djakov@kernel.org>