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_bedbug.c b/common/cmd_bedbug.c
index cd9e720..8be1c25 100644
--- a/common/cmd_bedbug.c
+++ b/common/cmd_bedbug.c
@@ -108,7 +108,7 @@
 
 U_BOOT_CMD (ds, 3, 1, do_bedbug_dis,
 	    "disassemble memory",
-	    "ds <address> [# instructions]\n");
+	    "ds <address> [# instructions]");
 
 /* ======================================================================
  * Entry point from the interpreter to the assembler.  Assembles
@@ -160,7 +160,7 @@
 }				/* do_bedbug_asm */
 
 U_BOOT_CMD (as, 2, 0, do_bedbug_asm,
-	    "assemble memory", "as <address>\n");
+	    "assemble memory", "as <address>");
 
 /* ======================================================================
  * Used to set a break point from the interpreter.  Simply calls into the
@@ -181,7 +181,7 @@
 	    " - Set or clear a breakpoint\n"
 	    "break <address> - Break at an address\n"
 	    "break off <bp#> - Disable breakpoint.\n"
-	    "break show      - List breakpoints.\n");
+	    "break show      - List breakpoints.");
 
 /* ======================================================================
  * Called from the debug interrupt routine.  Simply calls the CPU-specific
@@ -278,7 +278,7 @@
 
 U_BOOT_CMD (continue, 1, 0, do_bedbug_continue,
 	    "continue from a breakpoint",
-	    " - continue from a breakpoint.\n");
+	    "");
 
 /* ======================================================================
  * Interpreter command to continue to the next instruction, stepping into
@@ -309,7 +309,7 @@
 
 U_BOOT_CMD (step, 1, 1, do_bedbug_step,
 	    "single step execution.",
-	    " - single step execution.\n");
+	    "");
 
 /* ======================================================================
  * Interpreter command to continue to the next instruction, stepping over
@@ -340,7 +340,7 @@
 
 U_BOOT_CMD (next, 1, 1, do_bedbug_next,
 	    "single step execution, stepping over subroutines.",
-	    " - single step execution, stepping over subroutines.\n");
+	    "");
 
 /* ======================================================================
  * Interpreter command to print the current stack.  This assumes an EABI
@@ -385,7 +385,7 @@
 
 U_BOOT_CMD (where, 1, 1, do_bedbug_stack,
 	    "Print the running stack.",
-	    " - Print the running stack.\n");
+	    "");
 
 /* ======================================================================
  * Interpreter command to dump the registers.  Calls the CPU-specific
@@ -405,7 +405,7 @@
 }				/* do_bedbug_rdump */
 
 U_BOOT_CMD (rdump, 1, 1, do_bedbug_rdump,
-	    "Show registers.", " - Show registers.\n");
+	    "Show registers.", "");
 /* ====================================================================== */