Those structs are used only at bdisp-hw, so they shouldn't be
there in a header file that it is used elsewhere.

This fixes the following Gcc 6.1 warnings:

In file included from drivers/media/platform/sti/bdisp/bdisp-debug.c:11:0:
drivers/media/platform/sti/bdisp/bdisp-filter.h:207:65: warning: ‘bdisp_v_spec’ defined but not used [-Wunused-const-variable=]
 static const struct __maybe_unused bdisp_filter_v_spec bdisp_v_spec[] = {
                                                                 ^~~~~~~~~
In file included from drivers/media/platform/sti/bdisp/bdisp-debug.c:11:0:
drivers/media/platform/sti/bdisp/bdisp-filter.h:23:65: warning: ‘bdisp_h_spec’ defined but not used [-Wunused-const-variable=]
 static const struct __maybe_unused bdisp_filter_h_spec bdisp_h_spec[] = {
                                                                 ^~~~~~~~~
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>