arm: amx3xx: Add support for early debug

For early debug, the following configs needs to be enabled:

CONFIG_DEBUG_UART=y
CONFIG_DEBUG_UART_OMAP=y
CONFIG_DEBUG_UART_BASE=0x44e09000
CONFIG_DEBUG_UART_CLOCK=48000000
CONFIG_DEBUG_UART_SHIFT=2
CONFIG_DEBUG_UART_ANNOUNCE=y

Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

arch/arm/mach-omap2/am33xx/board.c

@@ -10,6 +10,7 @@
 
 #include <common.h>
 #include <dm.h>
+#include <debug_uart.h>
 #include <errno.h>
 #include <ns16550.h>
 #include <spl.h>
@@ -310,6 +311,9 @@ void early_system_init(void)
 	set_uart_mux_conf();
 	setup_early_clocks();
 	uart_soft_reset();
+#ifdef CONFIG_DEBUG_UART_OMAP
+	debug_uart_init();
+#endif
 #ifdef CONFIG_TI_I2C_BOARD_DETECT
 	do_board_detect();
 #endif