Cosmetic: Fix a number of typos, no functional changes.

Fix various misspellings of things like "environment", "kernel",
"default" and "volatile", and throw in a couple grammar fixes.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
diff --git a/include/configs/eXalion.h b/include/configs/eXalion.h
index c2d04a2..7321b60 100644
--- a/include/configs/eXalion.h
+++ b/include/configs/eXalion.h
@@ -119,7 +119,7 @@
 
 #define CONFIG_ENV_IS_IN_FLASH	1
 #define CONFIG_ENV_SECT_SIZE	0x20000 /* Size of one Flash sector */
-#define CONFIG_ENV_SIZE		CONFIG_ENV_SECT_SIZE	/* Use one Flash sector for enviroment	*/
+#define CONFIG_ENV_SIZE		CONFIG_ENV_SECT_SIZE	/* Use one Flash sector for environment	*/
 #define CONFIG_ENV_ADDR		0xFFFC0000
 #define CONFIG_ENV_OFFSET		0	/* starting right at the beginning  */