risc-v/mpfs: ihc: Make IHC HSS workaround configurable

arch/risc-v/src/mpfs/Kconfig

@@ -451,6 +451,13 @@ config MPFS_IHC_RPMSG_CH2
 		Use this only if using 2 x RPMSG channels.  This makes the NuttX work as the
 		RPMSG channel 2 client.
 
+config MPFS_IHC_WITH_HSS
+	bool "IHC with HSS"
+	depends on MPFS_IHC_CLIENT
+	default n
+	---help---
+		Set this to true if using IHC with HSS bootloader
+
 config MPFS_ETHMAC
 	bool
 	default n

arch/risc-v/src/mpfs/mpfs_ihc.c

@@ -169,7 +169,9 @@ static int mpfs_rptun_register_callback(struct rptun_dev_s *dev,
  * HSS.
  */
 
+#ifdef CONFIG_MPFS_IHC_WITH_HSS
 uint8_t unused_filler[0x80000] __attribute__((section(".filler_area")));
+#endif
 
 static struct rpmsg_endpoint       g_mpgs_echo_ping_ept;
 static struct mpfs_queue_table_s   g_mpfs_virtqueue_table[VRINGS];