qseecom: Fix clock get failures

Pass the device node with of_node to clk_get(), to get the clock struct.
This patch fixes the issue by passing proper device handle with of_node
to clock APIs to get the appropriate clock node.

Change-Id: I01a2caf7d86a4399b1bb4a455ef8ecbbad5ad9a2
Signed-off-by: AnilKumar Chimata <anilc@codeaurora.org>