hwspinlock: sirf: Change to use devm_platform_ioremap_resource()

Use the new helper that wraps the calls to platform_get_resource()
and devm_ioremap_resource() together, which can simpify the code.

Signed-off-by: Baolin Wang <baolin.wang7@gmail.com>
Link: https://lore.kernel.org/r/dfa043f317c609a6172468ac11598968dd751bce.1578453662.git.baolin.wang7@gmail.com


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