ti: k3: common: Make UART number configurable

This allows to build for k3-based boards that use a different UART as
console, such as the IOT2050 which requires K3_USART=1.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Change-Id: I7171f86c3cabae2c575b8fbeecef839b48bd109b

plat/ti/k3/common/plat_common.mk

@@ -37,6 +37,9 @@ ENABLE_PIE		:=	1
 TI_16550_MDR_QUIRK	:=	1
 $(eval $(call add_define,TI_16550_MDR_QUIRK))
 
+K3_USART		:=	0
+$(eval $(call add_define,K3_USART))
+
 # Allow customizing the UART baud rate
 K3_USART_BAUD		:=	115200
 $(eval $(call add_define,K3_USART_BAUD))

plat/ti/k3/include/platform_def.h

@@ -91,7 +91,7 @@
 
 /* Platform default console definitions */
 #ifndef K3_USART_BASE
-#define K3_USART_BASE 0x02800000
+#define K3_USART_BASE			(0x02800000 + 0x10000 * K3_USART)
 #endif
 
 /* USART has a default size for address space */