soc: swr-mstr: Fix KW issue in swrm_remove

irq_set_irq_data is used as argument to irq_set_trigger_type
which can be NULL. Check if irq_set_irq_data is NULL before
access.

Change-Id: I4832d65da22327d184b8a0927e84ff0ca4d40fad
Signed-off-by: Vatsal Bucha <vbucha@codeaurora.org>