git-gui: Remove unnecessary /dev/null redirection.

Git 1.5.0 and later no longer output useless messages to standard
error when making the initial (or what looks to be) commit of a
repository.  Since /dev/null does not exist on Windows in the
MinGW environment we can't redirect there anyway.  Since Git
does not output anymore, I'm removing the redirection.

Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

git-gui.sh

@@ -1299,14 +1299,8 @@ A rescan will be automatically started now.
 	# -- Create the commit.
 	#
 	set cmd [list git commit-tree $tree_id]
-	set parents [concat $PARENT $MERGE_HEAD]
-	if {[llength $parents] > 0} {
-		foreach p $parents {
-			lappend cmd -p $p
-		}
-	} else {
-		# git commit-tree writes to stderr during initial commit.
-		lappend cmd 2>/dev/null
+	foreach p [concat $PARENT $MERGE_HEAD] {
+		lappend cmd -p $p
 	}
 	lappend cmd <$msg_p
 	if {[catch {set cmt_id [eval exec $cmd]} err]} {