gicv2m_of_init() fails to perform an of_node_put() when
of_address_to_resource() fails, leading to a refcount leak.

Address this by moving the error handling path outside of the loop and
making it common to all failure modes.

Fixes: 4266ab1a ("irqchip/gic-v2m: Refactor to prepare for ACPI support")
Signed-off-by: Ma Ke <make24@iscas.ac.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/all/20240820092843.1219933-1-make24@iscas.ac.cn