tcl/board: drop 'tcl' prefix in 'find' command

tcl/board: drop 'tcl' prefix in 'find' command

When OpenOCD is installed to the host the 'tcl' folder gets
usually installed in /usr/share/openocd/, thus having 'tcl' as
prefix of the target's file causes 'find' to fail.

Remove the 'tcl' folder prefix.

Change-Id: I3dc484c8de6af8f5aae4dd1b230522ee47ae2ba6
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/5887
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>
Tested-by: jenkins