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/common/cmd_spi.c b/common/cmd_spi.c
index 1f0727b..746d14f 100644
--- a/common/cmd_spi.c
+++ b/common/cmd_spi.c
@@ -138,7 +138,7 @@
 
 U_BOOT_CMD(
 	sspi,	5,	1,	do_spi,
-	"sspi    - SPI utility commands\n",
+	"SPI utility commands",
 	"<device> <bit_len> <dout> - Send <bit_len> bits from <dout> out the SPI\n"
 	"<device>  - Identifies the chip select of the device\n"
 	"<bit_len> - Number of bits to send (base 10)\n"