ARM: keystone2: configs: Move SP to end of u-boot section

Currently u-boot stack is defined at the beginning of MSMC RAM.
This is a problem for uart boot mode as ROM downloads directly to
starting of MSMC RAM.
Fixing it by moving stack to the end of u-boot section and shifting
SYS_TEXT_BASE to the start of MSMC RAM.
Updated division of MSMC RAM is shown below:
	-----------------------------------------
	|		|	|		|
	| U-Boot text	|U-Boot	| SPL text	|
	| download	| Stack	| Download +	|
	|		|	| SPL_BSS +	|
	|		|	| SPL_STACK	|
	-----------------------------------------
	[1]		[2]	[3]		[4]

[1] SYS_TEXT_BASE (Start of MSMC RAM)
[2] SPL_TEXT_BASE - GBL_DATA_SIZE
[3] SPL_TEXT_BASE
[4] END of SPL

[1] + [2] is at least 1M on all platforms, so no chance of overlap.
Reviewed-by: NNishanth Menon <nm@ti.com>
Signed-off-by: NLokesh Vutla <lokeshvutla@ti.com>

include/configs/ti_armv7_keystone2.h

@@ -20,7 +20,7 @@
 /* SoC Configuration */
 #define CONFIG_ARCH_CPU_INIT
 #define CONFIG_SYS_ARCH_TIMER
-#define CONFIG_SYS_TEXT_BASE		0x0c001000
+#define CONFIG_SYS_TEXT_BASE		0x0c000000
 #define CONFIG_SPL_TARGET		"u-boot-spi.gph"
 #define CONFIG_SYS_DCACHE_OFF
 
@@ -29,7 +29,7 @@
 #define CONFIG_SYS_LPAE_SDRAM_BASE	0x800000000
 #define CONFIG_MAX_RAM_BANK_SIZE	(2 << 30)       /* 2GB */
 #define CONFIG_STACKSIZE		(512 << 10)     /* 512 KiB */
-#define CONFIG_SYS_INIT_SP_ADDR		(CONFIG_SYS_TEXT_BASE - \
+#define CONFIG_SYS_INIT_SP_ADDR		(CONFIG_SPL_TEXT_BASE - \
 					GENERATED_GBL_DATA_SIZE)
 
 /* SPL SPI Loader Configuration */