build

[common] add runtime detection and selection of AVX/AVX2 support #2409

Job	Run time
module	15s
client (gcc, g++, xdg-shell, Release)	44s
docs	50s
host-linux	23s
host-windows-cross	37s
client (gcc, g++, xdg-shell, Debug)	43s
host-windows-native	1m 3s
client (gcc, g++, libdecor, Release)	53s
obs (gcc)	26s
client (gcc, g++, libdecor, Debug)	35s
obs (clang)	39s
client (clang, clang++, xdg-shell, Release)	49s
client (clang, clang++, xdg-shell, Debug)	47s
client (clang, clang++, libdecor, Release)	47s
client (clang, clang++, libdecor, Debug)	41s
	10m 12s

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