msm: vidc: enable lossless encoding via debugfs

Add a new debugfs to enable/disable lossless encoding
manually. The enablement is set when setting capture port
format. Lossless encoding is only supported in AVC and HEVC
for now and RC_LOSSLESS is set. Encoder would skip other RC
modes setting.

Change-Id: I1f7c45ba8aa825d5445ae546148d08819a1f1aba
Signed-off-by: Shi Zhongbo <zhongbos@codeaurora.org>