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/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
index f80baeb..1c5e314 100644
--- a/drivers/gpio/pca953x.c
+++ b/drivers/gpio/pca953x.c
@@ -209,7 +209,7 @@
 
 U_BOOT_CMD(
 	pca953x,	5,	1,	do_pca953x,
-	"pca953x	- pca953x gpio access\n",
+	"pca953x gpio access",
 	"device [dev]\n"
 	"	- show or set current device address\n"
 #ifdef CONFIG_CMD_PCA953X_INFO