genirq/irq_sim: Check the return value of irq_sim_init() for error codes

As discussed with Marc Zyngier: irq_sim_init() and its devres variant
should return the base of the allocated interrupt range on success rather
than 0.

Make devm_irq_sim_init() check for an error code. This is a preparatory
change for modifying irq_sim_init() itself.

Change-Id: Id65d0c5c29d5527ab78858019a5ba399d678357c
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/20180304121018.640-3-brgl@bgdev.pl
Git-commit: 28b6afa7d4456e759031bf83706b4be3689fba94
Git-repo: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git


Signed-off-by: Vijay Navnath Kamble <vkambl@codeaurora.org>