General help message cleanup

Many of the help messages were not really helpful; for example, many
commands that take no arguments would not print a correct synopsis
line, but "No additional help available." which is not exactly wrong,
but not helpful either.

Commit ``Make "usage" messages more helpful.'' changed this
partially. But it also became clear that lots of "Usage" and "Help"
messages (fields "usage" and "help" in struct cmd_tbl_s respective)
were actually redundant.

This patch cleans this up - for example:

Before:
	=> help dtt
	dtt - Digital Thermometer and Thermostat

	Usage:
	dtt         - Read temperature from digital thermometer and thermostat.

After:
	=> help dtt
	dtt - Read temperature from Digital Thermometer and Thermostat

	Usage:
	dtt

Signed-off-by: Wolfgang Denk <wd@denx.de>
diff --git a/cpu/mpc512x/iim.c b/cpu/mpc512x/iim.c
index 6cdc422..8f2eb37 100644
--- a/cpu/mpc512x/iim.c
+++ b/cpu/mpc512x/iim.c
@@ -389,6 +389,6 @@
 	"			    no args for entire bank\n"
 	"fuse prog <frow_bit> 	- program fuse at row <frow>, bit <_bit>\n"
 	"			    <frow> is 0-31, <bit> is 0-7; eg. 13_2 \n"
-	"			  WARNING - this is permanent\n"
-	);
+	"			  WARNING - this is permanent"
+);
 #endif /* CONFIG_CMD_FUSE */