media: venc: don't use kernel-doc for undescribed enums

media: venc: don't use kernel-doc for undescribed enums

There are no descriptions for some enums, with produces lots
of warnings:

    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_LUMA' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_LUMA2' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_LUMA3' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_CHROMA' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_CHROMA2' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_CHROMA3' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_MV_INFO' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_BS_HEADER' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_PROB_BUF' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_RC_INFO' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_RC_CODE' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_RC_CODE2' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_RC_CODE3' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_vp8_if.c:55: warning: Enum value 'VENC_VP8_VPU_WORK_BUF_MAX' not described in enum 'venc_vp8_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:51: warning: Enum value 'VENC_H264_VPU_WORK_BUF_RC_INFO' not described in enum 'venc_h264_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:51: warning: Enum value 'VENC_H264_VPU_WORK_BUF_RC_CODE' not described in enum 'venc_h264_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:51: warning: Enum value 'VENC_H264_VPU_WORK_BUF_REC_LUMA' not described in enum 'venc_h264_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:51: warning: Enum value 'VENC_H264_VPU_WORK_BUF_REC_CHROMA' not described in enum 'venc_h264_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:51: warning: Enum value 'VENC_H264_VPU_WORK_BUF_REF_LUMA' not described in enum 'venc_h264_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:51: warning: Enum value 'VENC_H264_VPU_WORK_BUF_REF_CHROMA' not described in enum 'venc_h264_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:51: warning: Enum value 'VENC_H264_VPU_WORK_BUF_MV_INFO_1' not described in enum 'venc_h264_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:51: warning: Enum value 'VENC_H264_VPU_WORK_BUF_MV_INFO_2' not described in enum 'venc_h264_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:51: warning: Enum value 'VENC_H264_VPU_WORK_BUF_SKIP_FRAME' not described in enum 'venc_h264_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:51: warning: Enum value 'VENC_H264_VPU_WORK_BUF_MAX' not described in enum 'venc_h264_vpu_work_buf'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:60: warning: Enum value 'H264_BS_MODE_SPS' not described in enum 'venc_h264_bs_mode'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:60: warning: Enum value 'H264_BS_MODE_PPS' not described in enum 'venc_h264_bs_mode'
    drivers/media/platform/mtk-vcodec/venc/venc_h264_if.c:60: warning: Enum value 'H264_BS_MODE_FRAME' not described in enum 'venc_h264_bs_mode'

Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>