u-boot: Fix several typos

's/environemnt/environment/' and
	's/Environemnt/Environment/'

Signed-off-by: Shyam Saini <shyam@amarulasolutions.com>
diff --git a/include/configs/mx28evk.h b/include/configs/mx28evk.h
index f373b1e..dc4db2b 100644
--- a/include/configs/mx28evk.h
+++ b/include/configs/mx28evk.h
@@ -43,7 +43,7 @@
 		(CONFIG_ENV_OFFSET + CONFIG_ENV_RANGE)
 #endif
 
-/* Environemnt is in SPI flash */
+/* Environment is in SPI flash */
 #if defined(CONFIG_CMD_SF) && defined(CONFIG_ENV_IS_IN_SPI_FLASH)
 #define CONFIG_SYS_REDUNDAND_ENVIRONMENT
 #define CONFIG_ENV_OFFSET		0x40000		/* 256K */