[PATCH (GITK FIX)] gitk: Fix the "notflag: no such variable" error in --not processing.

Commit 2958228430b63f2e38c55519d1f98d8d6d9e23f3 fixed the switch statement used in option processing, which made some of the previously unreachable cases executable. This uncovered the fact that the variable used in the handling of the --not option is not initialized.

This patch initializes it. Note that actually it is also possible to remove it completely, because currently nobody uses the value.

Signed-off-by: Alexander Gavrilov <angavrilov@gmail.com>
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	On Monday 01 December 2008 19:29:53 Johannes Sixt wrote:
	> > $ git bisect view
	> > Error in startup script: can't read "notflag": no such variable
	> >     while executing
	> > "expr {!$notflag}"
	> >     ("--not" arm line 2)
	> >     invoked from within
	> > "switch -glob -- $arg {
	> >             "-d" -
	> >             "--date-order" {
	> >                 set vdatemode($n) 1
	> >                 # remove from origargs in case we hit an unknown option
	> >                 set origarg..."
	> >     (procedure "parseviewargs" line 21)
	> >     invoked from within
	> > "parseviewargs $view $args"
	> >     (procedure "start_rev_list" line 27)
	> >     invoked from within
	> > "start_rev_list $curview"
	> >     (procedure "getcommits" line 5)
	> >     invoked from within
	> > "getcommits {}"
	> >     (file "/usr/local/bin/gitk" line 10897)
	>
	> Bisection points to this commit:
	> 
	> commit 2958228430b63f2e38c55519d1f98d8d6d9e23f3

 gitk |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)