serial: drop redundant depends on

SANDBOX_SERIAL depends on SANDBOX, and SANDBOX selects DM.
So, "SANDBOX_SERIAL depends on DM" is redundant.

Likewise, UNIPHIER_SERIAL depends on ARCH_UNIPHIER, and
ARCH_UNIPHIER selects DM_SERIAL.
So, "UNIPHIER_SERIAL depends on DM_SERIAL" is redundant.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/serial/Kconfig b/drivers/serial/Kconfig
index 4f6a3b8..002f1da 100644
--- a/drivers/serial/Kconfig
+++ b/drivers/serial/Kconfig
@@ -111,7 +111,7 @@
 
 config SANDBOX_SERIAL
 	bool "Sandbox UART support"
-	depends on SANDBOX && DM
+	depends on SANDBOX
 	help
 	  Select this to enable a seral UART for sandbox. This is required to
 	  operate correctly, otherwise you will see no serial output from
@@ -131,7 +131,7 @@
 
 config UNIPHIER_SERIAL
 	bool "Support for UniPhier on-chip UART"
-	depends on ARCH_UNIPHIER && DM_SERIAL
+	depends on ARCH_UNIPHIER
 	help
 	  If you have a UniPhier based board and want to use the on-chip
 	  serial ports, say Y to this option. If unsure, say N.