helper/command: do not replace new commands with ocd_ prefix

The TCL return values are now consistent, no need anymore for the
hack of registering the commands with "ocd_" prefix and override
them with proc ocd_bouncer.

Clean-up the command registration and remove the proc ocd_bouncer.

This change was part of http://openocd.zylin.com/1815 from Paul
Fertser and has been extracted and rebased to simplify the review.

Change-Id: I2a467e73ecb068686ea3fda91bf961aba6db6427
Signed-off-by: Paul Fertser <fercerpav@gmail.com>
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/5086
Tested-by: jenkins

src/helper/startup.tcl

@@ -3,36 +3,6 @@
 # Embedded into OpenOCD executable
 #
 
-# All commands are registered with an 'ocd_' prefix, while the "real"
-# command is a wrapper that calls this function.  Its primary purpose is
-# to discard 'handler' command output.
-# Due to the two nested proc calls, this wrapper has to explicitly run
-# the wrapped command in the stack frame two levels above.
-proc ocd_bouncer {name args} {
-	set cmd [format "ocd_%s" $name]
-	set type [eval ocd_command type $cmd $args]
-	set errcode error
-	set skiplevel [expr [eval info level] > 1 ? 2 : 1]
-	if {$type == "native"} {
-		return [uplevel $skiplevel $cmd $args]
-	} else {if {$type == "simple"} {
-		set errcode [catch {uplevel $skiplevel $cmd $args}]
-		if {$errcode == 0} {
-			return ""
-		} else {
-			# 'classic' commands output error message as part of progress output
-			set errmsg ""
-		}
-	} else {if {$type == "group"} {
-		catch {eval ocd_usage $name $args}
-		set errmsg [format "%s: command requires more arguments" \
-			[concat $name " " $args]]
-	} else {
-		set errmsg [format "invalid subcommand \"%s\"" $args]
-	}}}
-	return -code $errcode $errmsg
-}
-
 # Try flipping / and \ to find file if the filename does not
 # match the precise spelling
 proc find {filename} {