drm: remove no longer needed drm-get-put coccinelle script

The coccinelle script was used to rename some (deprecated) functions
which no longer exist now.

Signed-off-by: Fernando Ramos <greenfoo@gluegarage.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20181115221634.22715-9-greenfoo@gluegarage.com