dynamic-debug-howto: fix optional/omitted ending line number to be LARGE instead...

dynamic-debug-howto: fix optional/omitted ending line number to be LARGE instead of 0

line-range is supposed to treat "1-" as "1-endoffile", so
handle the special case by setting last_lineno to UINT_MAX.

Fixes this error:

  dynamic_debug:ddebug_parse_query: last-line:0 < 1st-line:1
  dynamic_debug:ddebug_exec_query: query parse failed

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Randy Dunlap <[email protected]>
Acked-by: Jason Baron <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>