Set dma max segment size for encoder and decoder driver.

Fix following warning with CONFIG_DMA_API_DEBUG_SG=y

[   75.147825] ------------[ cut here ]------------
[   75.147844] mtk-vcodec-enc 19002000.vcodec: DMA-API: mapping sg segment longer than device claims to support [len=983040] [max=65536]
[   75.147876] WARNING: CPU: 2 PID: 4069 at kernel/dma/debug.c:1302 debug_dma_map_sg+0x1a8/0x2c4
...
[   75.148139] Call trace:
[   75.148149]  debug_dma_map_sg+0x1a8/0x2c4
[   75.148165]  vb2_dc_get_userptr+0x228/0x364 [videobuf2_dma_contig]
[   75.148178]  __buf_prepare+0x3ac/0x8c0 [videobuf2_common]
[   75.148188]  vb2_core_qbuf+0xa4/0x58c [videobuf2_common]
[   75.148199]  vb2_qbuf+0x88/0xe4 [videobuf2_v4l2]
[   75.148211]  v4l2_m2m_qbuf+0x80/0xf8 [v4l2_mem2mem]
[   75.148221]  vidioc_venc_qbuf+0x3c/0x70 [mtk_vcodec_enc]
[   75.148234]  v4l_qbuf+0x48/0x58
[   75.148242]  __video_do_ioctl+0x200/0x37c
[   75.148250]  video_usercopy+0x360/0x834
[   75.148259]  video_ioctl2+0x38/0x48
[   75.148267]  v4l2_ioctl+0x6c/0x80
[   75.148276]  do_video_ioctl+0xefc/0x4b70
[   75.148284]  v4l2_compat_ioctl32+0x5c/0xcc
[   75.148294]  __arm64_compat_sys_ioctl+0xf4/0x240
[   75.148304]  el0_svc_common+0xac/0x198
[   75.148312]  el0_svc_compat_handler+0x2c/0x40
[   75.148321]  el0_svc_compat+0x8/0x18
[   75.148328] irq event stamp: 0
[   75.148337] hardirqs last  enabled at (0): [<0000000000000000>]           (null)
[   75.148347] hardirqs last disabled at (0): [<ffffff90080e65c0>] copy_process+0x380/0x115c
[   75.148356] softirqs last  enabled at (0): [<ffffff90080e65d8>] copy_process+0x398/0x115c
[   75.148364] softirqs last disabled at (0): [<0000000000000000>]           (null)
[   75.148372] ---[ end trace 588bf529451e3531 ]---
Reported-by: Anand K Mistry <amistry@chromium.org>
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>