increasing the chip task size for the 917soc (#35213)

diff --git a/src/platform/silabs/CHIPDevicePlatformConfig.h b/src/platform/silabs/CHIPDevicePlatformConfig.h
index 091940b..010d72e 100644
--- a/src/platform/silabs/CHIPDevicePlatformConfig.h
+++ b/src/platform/silabs/CHIPDevicePlatformConfig.h
@@ -130,7 +130,11 @@
 // ========== Platform-specific Configuration Overrides =========
 
 #ifndef CHIP_DEVICE_CONFIG_CHIP_TASK_STACK_SIZE
+#if SLI_SI91X_MCU_INTERFACE
+#define CHIP_DEVICE_CONFIG_CHIP_TASK_STACK_SIZE (7 * 1024)
+#else
 #define CHIP_DEVICE_CONFIG_CHIP_TASK_STACK_SIZE (6 * 1024)
+#endif
 #endif // CHIP_DEVICE_CONFIG_CHIP_TASK_STACK_SIZE
 
 #ifndef CHIP_DEVICE_CONFIG_THREAD_TASK_STACK_SIZE