soc: microchip: sam: update NUM_IRQS default value for sama7g5

Enlarge NUM_IRQS by 32 which is the number of interrupts for
SGI (Software Generated Interrupts) and PPI (Private Peripheral
Interrupts).

Signed-off-by: Tony Han <tony.han@microchip.com>

Author: TonyHan11

soc/microchip/sam/sama7g5/Kconfig.defconfig

@@ -6,7 +6,7 @@
 if SOC_SERIES_SAMA7G5
 
 config NUM_IRQS
-	default 155
+	default 187
 
 config SYS_CLOCK_HW_CYCLES_PER_SEC
 	default $(dt_node_int_prop_int,/soc/timer@e1800000,clock-frequency)