Saturate additions in getEnvSfbEnergy in SBR encoding #31

Job	Run time
linux-sanitizers-clang-cmake	2m 20s
linux-cmake	1m 37s
linux-autotools	1m 31s
linux-ffmpeg	5m 12s
linux-sanitizers-gcc-autotools	5m 13s
llvm-mingw	1m 31s
macos-autotools	1m 52s
macos-cmake	2m 4s
mingw-cross-autotools	1m 13s
msvc-cmake	57s
mingw-cross-cmake	1m 20s
msvc-cmake-arm64	1m 52s
msvc-cmake-ninja-arm	1m 33s
msys-cmake	2m 18s
	30m 33s

Provide feedback