mtd: Kconfig: Change HBMC driver's dependency to MULTIPLEXER and MUX_MMIO

The HBMC_AM654 driver was dependent on SYSCON because syscon APIs were
being used to select the multiplexer state. Change the dependency to
MULTIPLEXER and MUX_MMIO because mux APIs are now being used to
select mux state.

Signed-off-by: Anurag Dutta <a-dutta@ti.com>
diff --git a/drivers/mtd/Kconfig b/drivers/mtd/Kconfig
index 3764e25..678bbde 100644
--- a/drivers/mtd/Kconfig
+++ b/drivers/mtd/Kconfig
@@ -202,7 +202,7 @@
 
 config HBMC_AM654
 	bool "HyperBus controller driver for AM65x SoC"
-	depends on SYSCON
+	depends on MULTIPLEXER && MUX_MMIO
 	help
 	 This is the driver for HyperBus controller on TI's AM65x and
 	 other SoCs