crypto: omap-aes - Convert request_irq to devm_request_irq

Keeps request_irq exit/error code paths simpler.

Suggested-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Joel Fernandes <joelf@ti.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>