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/common/cmd_load.c b/common/cmd_load.c
index 2b5a66d..73fbf74 100644
--- a/common/cmd_load.c
+++ b/common/cmd_load.c
@@ -1049,7 +1049,7 @@
 	"load S-Record file over serial line",
 	"[ off ] [ baud ]\n"
 	"    - load S-Record file over serial line"
-	" with offset 'off' and baudrate 'baud'\n"
+	" with offset 'off' and baudrate 'baud'"
 );
 
 #else	/* ! CONFIG_SYS_LOADS_BAUD_CHANGE */
@@ -1057,7 +1057,7 @@
 	loads, 2, 0,	do_load_serial,
 	"load S-Record file over serial line",
 	"[ off ]\n"
-	"    - load S-Record file over serial line with offset 'off'\n"
+	"    - load S-Record file over serial line with offset 'off'"
 );
 #endif	/* CONFIG_SYS_LOADS_BAUD_CHANGE */
 
@@ -1073,14 +1073,14 @@
 	"save S-Record file over serial line",
 	"[ off ] [size] [ baud ]\n"
 	"    - save S-Record file over serial line"
-	" with offset 'off', size 'size' and baudrate 'baud'\n"
+	" with offset 'off', size 'size' and baudrate 'baud'"
 );
 #else	/* ! CONFIG_SYS_LOADS_BAUD_CHANGE */
 U_BOOT_CMD(
 	saves, 3, 0,	do_save_serial,
 	"save S-Record file over serial line",
 	"[ off ] [size]\n"
-	"    - save S-Record file over serial line with offset 'off' and size 'size'\n"
+	"    - save S-Record file over serial line with offset 'off' and size 'size'"
 );
 #endif	/* CONFIG_SYS_LOADS_BAUD_CHANGE */
 #endif
@@ -1093,7 +1093,7 @@
 	"load binary file over serial line (kermit mode)",
 	"[ off ] [ baud ]\n"
 	"    - load binary file over serial line"
-	" with offset 'off' and baudrate 'baud'\n"
+	" with offset 'off' and baudrate 'baud'"
 );
 
 U_BOOT_CMD(
@@ -1101,7 +1101,7 @@
 	"load binary file over serial line (ymodem mode)",
 	"[ off ] [ baud ]\n"
 	"    - load binary file over serial line"
-	" with offset 'off' and baudrate 'baud'\n"
+	" with offset 'off' and baudrate 'baud'"
 );
 
 #endif
@@ -1130,8 +1130,8 @@
 
 U_BOOT_CMD(
 	hwflow, 2, 0,	do_hwflow,
-	"turn the harwdare flow control on/off",
-	"[on|off]\n - change RTS/CTS hardware flow control over serial line\n"
+	"turn RTS/CTS hardware flow control in serial line on/off",
+	"[on|off]"
 );
 
 #endif