Command usage cleanup

Remove command name from all command "usage" fields and update
common/command.c to display "name - usage" instead of
just "usage". Also remove newlines from command usage fields.

Signed-off-by: Peter Tyser <ptyser@xes-inc.com>
diff --git a/board/amcc/makalu/cmd_pll.c b/board/amcc/makalu/cmd_pll.c
index 3b49e5b..6b38493 100644
--- a/board/amcc/makalu/cmd_pll.c
+++ b/board/amcc/makalu/cmd_pll.c
@@ -237,7 +237,7 @@
 
 U_BOOT_CMD(
 	pllalter, CONFIG_SYS_MAXARGS, 1,        do_pll_alter,
-	"pllalter- change pll frequence \n",
+	"change pll frequence",
 	"pllalter <selection>      - change pll frequence \n\n\
 	** New freq take effect after reset. ** \n\
 	----------------------------------------------\n\