util/sconfig/main.c: Remove assigned but unused variable `link`

Cppcheck 1.65 report the style style issue below.

	[main.c:434]: (style) Variable 'link' is assigned a value that is never used.

So remove the variable `link` as it is not needed.

Change-Id: Ib77b80b74a70985a76eaa3247c4a43832ef23a59
Signed-off-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-on: http://review.coreboot.org/6488
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>
sconfig: improve argument parsing

Running sconfig with four arguments where the third
does not match /-./ made sconfig use uninitialized
memory to build the output filename.

Change-Id: If4a147ff23771ca9b6a913605af60249be1ca3d0
Found-By: Coverity Scan
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-on: http://review.coreboot.org/6483
Tested-by: build bot (Jenkins)
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>