ARM: socfpga: Convert to DM serial

Pull the serial port configuration from DT and use DM serial instead
of having the serial configuration in two places, DT and board config.

Signed-off-by: Marek Vasut <marex@denx.de>
Cc: Chin Liang See <chin.liang.see@intel.com>
Cc: Dinh Nguyen <dinguyen@kernel.org>

arch/arm/Kconfig

@@ -737,6 +737,7 @@ config ARCH_SOCFPGA
 	select ARCH_MISC_INIT
 	select CPU_V7A
 	select DM
+	select DM_SERIAL
 	select ENABLE_ARM_SOC_BOOT0_HOOK
 	select OF_CONTROL
 	select SPL_LIBCOMMON_SUPPORT
@@ -746,11 +747,13 @@ config ARCH_SOCFPGA
 	select SPL_NAND_SUPPORT if SPL_NAND_DENALI
 	select SPL_OF_CONTROL
 	select SPL_SERIAL_SUPPORT
+	select SPL_DM_SERIAL
 	select SPL_SPI_FLASH_SUPPORT if SPL_SPI_SUPPORT
 	select SPL_SPI_SUPPORT if DM_SPI
 	select SPL_WATCHDOG_SUPPORT
 	select SUPPORT_SPL
 	select SYS_MMCSD_RAW_MODE_U_BOOT_USE_PARTITION_TYPE
+	select SYS_NS16550
 	select SYS_THUMB_BUILD
 	imply CMD_MTDPARTS
 	imply CRC32_VERIFY

arch/arm/dts/socfpga.dtsi

@@ -737,6 +737,7 @@
 			reg-shift = <2>;
 			reg-io-width = <4>;
 			clocks = <&l4_sp_clk>;
+			clock-frequency = <100000000>;
 		};
 
 		uart1: serial1@ffc03000 {
@@ -746,6 +747,7 @@
 			reg-shift = <2>;
 			reg-io-width = <4>;
 			clocks = <&l4_sp_clk>;
+			clock-frequency = <100000000>;
 		};
 
 		rst: rstmgr@ffd05000 {

arch/arm/dts/socfpga_arria10_socdk_sdmmc.dts

@@ -24,6 +24,7 @@
 };
 
 &uart1 {
+	clock-frequency = <50000000>;
 	u-boot,dm-pre-reloc;
 	status = "okay";
 };

include/configs/socfpga_common.h

@@ -173,14 +173,6 @@ unsigned int cm_get_qspi_controller_clk_hz(void);
  * Serial Driver
  */
 #define CONFIG_SYS_NS16550_SERIAL
-#define CONFIG_SYS_NS16550_REG_SIZE	-4
-#if defined(CONFIG_TARGET_SOCFPGA_GEN5)
-#define CONFIG_SYS_NS16550_COM1		SOCFPGA_UART0_ADDRESS
-#define CONFIG_SYS_NS16550_CLK		100000000
-#elif defined(CONFIG_TARGET_SOCFPGA_ARRIA10)
-#define CONFIG_SYS_NS16550_COM1        SOCFPGA_UART1_ADDRESS
-#define CONFIG_SYS_NS16550_CLK		50000000
-#endif
 
 /*
  * USB