[media] anysee: make sure loading modules is const

Make sure that loaded modules are const char strings so we don't
load arbitrary modules in the future, nor allow for format string
leaks in the module request call.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>