Use correct spelling of "U-Boot"

Correct spelling of "U-Boot" shall be used in all written text
(documentation, comments in source files etc.).

Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
Reviewed-by: Heiko Schocher <hs@denx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Minkyu Kang <mk7.kang@samsung.com>
diff --git a/board/freescale/mx35pdk/README b/board/freescale/mx35pdk/README
index 7232b53..6f6841f 100644
--- a/board/freescale/mx35pdk/README
+++ b/board/freescale/mx35pdk/README
@@ -71,7 +71,7 @@
 Flashing U-Boot
 --------------------------------
 
-U-boot should be stored on the NOR flash.
+U-Boot should be stored on the NOR flash.
 
 The boot storage can be select using the switches on the personality board
 (SW1-SW2) and on the DEBUG board (SW4-SW10).
@@ -96,7 +96,7 @@
 To erase the whole partition:
 $ flash_eraseall /dev/mtd0
 
-Writing u-boot:
+Writing U-Boot:
 dd if=u-boot.bin of=/dev/mtd0
 
 To boot from NOR, you have to select the switches as follows: