i.MX31: Correct comments on CONFIG_DEBUG_LL.

Several comments in board config files stated "mandatory for
CONFIG_LL_DEBUG" but the correct name is CONFIG_DEBUG_LL.

Signed-off-by: Magnus Lilja <lilja.magnus@gmail.com>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
diff --git a/arch/arm/plat-mxc/include/mach/board-pcm037.h b/arch/arm/plat-mxc/include/mach/board-pcm037.h
index 82232ba..f0a1fa1 100644
--- a/arch/arm/plat-mxc/include/mach/board-pcm037.h
+++ b/arch/arm/plat-mxc/include/mach/board-pcm037.h
@@ -19,7 +19,7 @@
 #ifndef __ASM_ARCH_MXC_BOARD_PCM037_H__
 #define __ASM_ARCH_MXC_BOARD_PCM037_H__
 
-/* mandatory for CONFIG_LL_DEBUG */
+/* mandatory for CONFIG_DEBUG_LL */
 
 #define MXC_LL_UART_PADDR	UART1_BASE_ADDR
 #define MXC_LL_UART_VADDR	AIPS1_IO_ADDRESS(UART1_BASE_ADDR)