irqchip/mips-gic: Fix selection of GENERIC_IRQ_EFFECTIVE_AFF_MASK

Without SMP enabled (such as in allnoconfig), there is a Kconfig warning
because CONFIG_IRQ_EFFECTIVE_AFF_MASK is unconditionally selected by
CONFIG_MIPS_GIC:

  WARNING: unmet direct dependencies detected for GENERIC_IRQ_EFFECTIVE_AFF_MASK
    Depends on [n]: SMP [=n]
    Selected by [y]:
    - MIPS_GIC [=y]

Add a dependency on SMP to the selection, which matches all other
selections of CONFIG_IRQ_EFFECTIVE_AFF_MASK.

Fixes: 322a906 ("irqchip/mips-gic: Multi-cluster support")
Signed-off-by: Nathan Chancellor <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/all/20241101-mips-fix-generic_irq_effective_aff_mask-select-v1-1-d94db6e0de0d@kernel.org

Author: nathanchance

drivers/irqchip/Kconfig

@@ -352,7 +352,7 @@ config KEYSTONE_IRQ
 
 config MIPS_GIC
 	bool
-	select GENERIC_IRQ_EFFECTIVE_AFF_MASK
+	select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
 	select GENERIC_IRQ_IPI if SMP
 	select IRQ_DOMAIN_HIERARCHY
 	select MIPS_CM