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>

1 files changed, 2 insertions, 1 deletions

diff --git a/common/cmd_strings.c b/common/cmd_strings.c
index 4517ba2..3a0d8ff 100644
--- a/common/cmd_strings.c
+++ b/common/cmd_strings.c
@@ -43,4 +43,5 @@ int do_strings(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
 U_BOOT_CMD(strings, 3, 1, do_strings,
 	"display strings",
 	"<addr> [byte count]\n"
-	"    - display strings at <addr> for at least [byte count] or first double NUL\n");
+	"    - display strings at <addr> for at least [byte count] or first double NUL"
+);