Heavily inspired off linux kernel's dynamic debug:
* add a /sys/kernel/debug/dynamic_debug/control file
(accessible from linux side in /sys/class/mcos/mcos0/sys/kernel/debug/dynamic_debug/control)
* read from file to list debug statements (currently limited to 4k in size)
* write to file with '[file foo ][func bar ][line [x][-[y]]] [+-]p' to change values
Side effects:
* reindented all linker scripts, there is a new __verbose section
* added string function strpbrk
Change-Id: I36d7707274dcc3ecaf200075a31a2f0f76021059
Parameters of dkprintf() should be evaluated even if dkprintf() is
disabled. Because this enables to find expression of parameter obsolete
and to avoid unnecessary compiler warnings such as "unused variable".