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/examples/standalone/smc911x_eeprom.c b/examples/standalone/smc911x_eeprom.c
index 364ad2d..2c05ed9 100644
--- a/examples/standalone/smc911x_eeprom.c
+++ b/examples/standalone/smc911x_eeprom.c
@@ -9,7 +9,7 @@
  * Based on smc91111_eeprom.c which:
  * Heavily borrowed from the following peoples GPL'ed software:
  *  - Wolfgang Denk, DENX Software Engineering, wd@denx.de
- *       Das U-boot
+ *       Das U-Boot
  *  - Ladislav Michl ladis@linux-mips.org
  *       A rejected patch on the U-Boot mailing list
  */