soc: cva6: Fix CONFIG_MAX_IRQ_PER_AGGREGATOR

The original commit uses the incorrect value 42 for
CONFIG_MAX_IRQ_PER_AGGREGATOR for the cva6 family of SoCs,
which is the total number of IRQs in the system.
This commit corrects this to 30, the number of IRQs for the PLIC.

Signed-off-by: Eric Ackermann <eric.ackermann@cispa.de>

Author: WorldofJARcraft

soc/openhwgroup/cva6/Kconfig.defconfig

@@ -19,7 +19,7 @@ config 2ND_LVL_INTR_00_OFFSET
 
 # 12 first level, 30 second level
 config MAX_IRQ_PER_AGGREGATOR
-	default 42
+	default 30
 
 # one 2nd level aggregator (PLIC) with 30 interrupts
 # offset of 12