media: davinci: fix kernel-doc warnings

media: davinci: fix kernel-doc warnings

There are several of kernel-doc warnings:

    drivers/media/platform/davinci/vpif_display.c:114: warning: No description found for parameter 'sizes'
    drivers/media/platform/davinci/vpif_display.c:165: warning: No description found for parameter 'vq'
    drivers/media/platform/davinci/vpif_display.c:165: warning: Excess function parameter 'vb' description in 'vpif_start_streaming'
    drivers/media/platform/davinci/vpif_display.c:780: warning: No description found for parameter 'vpif_cfg'
    drivers/media/platform/davinci/vpif_display.c:780: warning: No description found for parameter 'chan_cfg'
    drivers/media/platform/davinci/vpif_display.c:780: warning: No description found for parameter 'index'
    drivers/media/platform/davinci/vpif_display.c:813: warning: No description found for parameter 'vpif_cfg'
    drivers/media/platform/davinci/vpif_display.c:813: warning: No description found for parameter 'ch'
    drivers/media/platform/davinci/vpif_display.c:813: warning: No description found for parameter 'index'
    drivers/media/platform/davinci/vpif_capture.c:121: warning: No description found for parameter 'sizes'
    drivers/media/platform/davinci/vpif_capture.c:174: warning: No description found for parameter 'vq'
    drivers/media/platform/davinci/vpif_capture.c:174: warning: Excess function parameter 'vb' description in 'vpif_start_streaming'
    drivers/media/platform/davinci/vpif_capture.c:636: warning: No description found for parameter 'iface'
    drivers/media/platform/davinci/vpif_capture.c:647: warning: No description found for parameter 'ch'
    drivers/media/platform/davinci/vpif_capture.c:647: warning: No description found for parameter 'muxmode'
    drivers/media/platform/davinci/vpif_capture.c:676: warning: No description found for parameter 'vpif_cfg'
    drivers/media/platform/davinci/vpif_capture.c:676: warning: No description found for parameter 'chan_cfg'
    drivers/media/platform/davinci/vpif_capture.c:676: warning: No description found for parameter 'input_index'
    drivers/media/platform/davinci/vpif_capture.c:712: warning: No description found for parameter 'vpif_cfg'
    drivers/media/platform/davinci/vpif_capture.c:712: warning: No description found for parameter 'ch'
    drivers/media/platform/davinci/vpif_capture.c:712: warning: No description found for parameter 'index'
    drivers/media/platform/davinci/vpif_capture.c:798: warning: No description found for parameter 'std'
    drivers/media/platform/davinci/vpif_capture.c:798: warning: Excess function parameter 'std_id' description in 'vpif_g_std'
    drivers/media/platform/davinci/vpif_capture.c:940: warning: No description found for parameter 'fmt'
    drivers/media/platform/davinci/vpif_capture.c:940: warning: Excess function parameter 'index' description in 'vpif_enum_fmt_vid_cap'
    drivers/media/platform/davinci/vpif_capture.c:1750: warning: No description found for parameter 'dev'

Fix them.

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