irqchip: gic: Perform the gic_secondary_init() call via CPU notifier

All the calls to gic_secondary_init() pass 0 as the first argument.
Since this function is called on each CPU when starting, it can be done
in a platform-independent way via a CPU notifier registered by the GIC
code.

Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Acked-by: Rob Herring <rob.herring@calxeda.com>
Acked-by: Simon Horman <horms+renesas@verge.net.au>
Tested-by: Simon Horman <horms+renesas@verge.net.au>
Acked-by: Srinidhi Kasagar <srinidhi.kasagar@stericsson.com>
Tested-by: Dinh Nguyen <dinguyen@altera.com>
Acked-by: Nicolas Pitre <nico@linaro.org>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Russell King <linux@arm.linux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Sascha Hauer <kernel@pengutronix.de>
Cc: David Brown <davidb@codeaurora.org>
Cc: Bryan Huntsman <bryanh@codeaurora.org>
Cc: Tony Lindgren <tony@atomide.com>
Cc: Magnus Damm <magnus.damm@gmail.com>
Cc: Shiraz Hashim <shiraz.hashim@st.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Kukjin Kim <kgene.kim@samsung.com>
Cc: Barry Song <baohua.song@csr.com>