script: support only Tcl comments

script: support only Tcl comments

Only Tcl comments are now supported. For classic style
commands comments were supported at the end of the line.

Move in the direction of letting the script language
decide syntax, rather than have special rules for some
commands.

Before this patch goes in, the scripts should be updated
to use ;# instead of # for end of line comments.

> mdw 0 1 2
mdw ['phys'] address [count]
  zy1000.cpu mdw address [count]
Command handler execution failed
in procedure 'mdw'
> mdw 0 1 #2
mdw ['phys'] address [count]
  zy1000.cpu mdw address [count]
Command handler execution failed
in procedure 'mdw'
> mdw 0 1 ;#2
0x00000000: ffffffff
> mdw 0 1
0x00000000: ffffffff
> mdw 0
0x00000000: ffffffff

Signed-off-by: Øyvind Harboe <oyvind.harboe@zylin.com>