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_mfsl.c b/common/cmd_mfsl.c
index 6470bac..b19ad0e 100644
--- a/common/cmd_mfsl.c
+++ b/common/cmd_mfsl.c
@@ -394,8 +394,7 @@
 		" 0 - non blocking data read\n"
 		" 1 - non blocking control read\n"
 		" 2 - blocking data read\n"
-		" 3 - blocking control read\n");
-
+		" 3 - blocking control read");
 
 U_BOOT_CMD (fwr, 4, 1, do_fwr,
 		"write data to FSL",
@@ -403,11 +402,11 @@
 		" 0 - non blocking data write\n"
 		" 1 - non blocking control write\n"
 		" 2 - blocking data write\n"
-		" 3 - blocking control write\n");
+		" 3 - blocking control write");
 
 U_BOOT_CMD (rspr, 3, 1, do_rspr,
 		"read/write special purpose register",
 		"- reg_num [write value] read/write special purpose register\n"
 		" 1 - MSR - Machine status register\n"
 		" 3 - EAR - Exception address register\n"
-		" 5 - ESR - Exception status register\n");
+		" 5 - ESR - Exception status register");