qcom: cpuss_dump: Do not return error if parsing child nodes fails

Failure to parse the child nodes of the cpuss_dump node is not
fatal, and the code continues to parse the remaining child nodes
without returning the error code, else the driver will not be
probed successfully. The function should return zero after all
the nodes have been parsed.

Change-Id: Ibed26fae53b3b3029f090191ca2d7cfd21e979f0
Signed-off-by: Neeti Desai <neetid@codeaurora.org>