wcnss: Adding entry for new iris card WCN3615

Adding entry for new iris card WCN3615 and adding fix for getting wrong
iris card chip id. In wcnss_get_iris_name, when iris_id shifts 16bits
right, it can't match the right name as the highest bit is filled up
with 1.

Change type of iris_id from int to u32, and add mask for iris_id.

Change-Id: Ic7b334aa0b3f018fe915f6d0e96b6f9605492459
Signed-off-by: Sandeep Singh <sandsing@codeaurora.org>