target-mips/translate.c: Free TCG in OPC_DINSV

Free t0 and t1 in opcode OPC_DINSV.

Signed-off-by: Dongxue Zhang <elta.era@gmail.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
po: Update German translation

Line numbers changed, and some translations were missing after commit
3d914488aee3dc1bf495e461aedf8fb4e5bb2270.

Update also "Show Tabs" to a more common translation, and remove some
old unused lines at the end.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>