Set default configuration for realtime usage (--rt)

[jianj-g]

Add default extra and encoder configuration options for AVM_USAGE_REALTIME in av2/av2_cx_iface.c to match standard RTC encoding defaults, and simplify test/rtc_test.cc to use the new defaults.

Setting --rt in the avmenc command line applies standard Realtime (RTC) defaults equivalent to:

--bit-depth=8 --passes=1 --lag-in-frames=0 --auto-alt-ref=0 --enable-tpl-model=0 \
--enable-keyframe-filtering=0 --enable-deblocking=1 --enable-restoration=0 \
--enable-intra-edge-filter=0 --enable-flip-idtx=1 --enable-masked-comp=0 \
--enable-onesided-comp=0 --enable-interintra-comp=0 --enable-smooth-interintra=0 \
--enable-diff-wtd-comp=0 --enable-interinter-wedge=0 --enable-interintra-wedge=0 \
--enable-global-motion=0 --enable-warped-motion=0 --enable-smooth-intra=0 \
--enable-paeth-intra=0 --enable-cfl-intra=0 --force-video-mode=1 --enable-overlay=0 \
--enable-angle-delta=0 --enable-trellis-quant=0 --enable-qm=0 --use-intra-dct-only=1 \
--coeff-cost-upd-freq=2 --mode-cost-upd-freq=2 --mv-cost-upd-freq=3 --frame-parallel=0 \
--aq-mode=0 --deltaq-mode=0 --frame-boost=0 --noise-sensitivity=0 --cdf-update-mode=1 \
--reduced-reference-set=1 --enable-ref-frame-mvs=0 --erp-pruning-level=0 \
--use-ml-erp-pruning=0 --enable-ext-partitions=0 --enable-mrls=0 --enable-pc-wiener=0 \
--enable-wiener-nonsep=0 --enable-tip=0 --enable-bawp=0 --enable-cwp=0 \
--enable-imp-msk-bld=0 --enable-ist=0 --enable-inter-ist=0 --enable-inter-ddt=0 \
--enable-cctx=0 --enable-ibp=0 --max-drl-refmvs=0 --max-drl-refbvs=0 --enable-refmvbank=0 \
--enable-opfl-refine=0 --enable-ccso=0 --enable-lf-sub-pu=0 --enable-adaptive-mvd=0 \
--enable-flex-mvres=0 --enable-joint-mvd=0 --enable-refinemv=0 --enable-mvd-sign-derive=0 \
--enable-parity-hiding=0 --enable-warp-delta=0 --enable-warp-extend=0 --tile-columns=0 \
--gf-min-pyr-height=0 --gf-max-pyr-height=0 --enable-sdp=0 --min-gf-interval=8 \
--max-gf-interval=8 --explicit-ref-frame-map=1 --enable-bru=0 --enable-ext-seg=0 \
--enable-six-param-warp-delta=0 --enable-cdef=1 --enable-cdef-on-skip-txfm=0 \
--dpb-size=8 --use-inter-dct-only=0 --enable-fsc=1 --enable-idtx-intra=1 \
--enable-palette=1 --enable-intrabc-ext=0 --enable-intrabc=1 --cpu-used=6 \
--enable-gdf=0 --max-reference-frames=3

[marpan-max]

For reference, can you put the avmenc command line this RTC default config corresponds to?

[jianj-g]

For reference, can you put the avmenc command line this RTC default config corresponds to?

Added the typical RTC command line in commit message.