media: vidc: added encoder part of the driver

This contains many changes apart the encoder part, the
detailed list follow:

 - don't check input args, the caller will take care of
 - use one mutex in venus hfi code
 - correct returned errors
 - delete firmware operations from hfi ops structure
 - reorder ops and make static
 - rename hfi op from power_enable to resume
 - delete non informative error prints and rework core_init
 - code reordering and cleanups
 - call vb2 done on buf_queue if error occurs
 - clear firmware booted flag on unload
 - rename vidc_comm_suspend to hfi_core_suspend
 - reduce number of instance states
 - return exact error on session_init
 - don't touch videobuf-core queue fields
 - inst->fmts[OUTPUT_PORT] to fmt_cap & fmt_out
 - delete few not needed calls and a cleanup
 - add struct vidc_core as first arg of event_notify
 - set directly default parameters
 - add vdec_try_fmt and bunch of cleanups
 - create venus_run function to setup regs and reset venus core
 - bunch of cleanups again
 - delete with_out|cap and fix try_fmt, and even more changes
 - cleanup in s_fmt
 - use hfi_session_set_property instead of direct call save some space
 - rework hfi_session_prop_info
 - cleanups, cleanups
 - delete vidc_session_prop struct and save some code
 - add video encoder files but don't build them for now!
 - build encoder and fix few compile errors/warnings
 - reorder functions in decoder to match with encoder
 - fix querycap and dev_info->dev_dbg
 - changes in clks and loading, move clk scaling in common place
 - many changes in s_fmt/try_fmt and s_ctrl
 - merge ext controls in s_ctrl in venc ctrls

Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>