Optimize CRC intrinisics for targets lacking of CRC extension #45

Job	Run time
coding-style	8s
host-win-msvc	1m 17s
host-win (x86_64)	41s
host-arm (armv7, none, none, g++-10)	3m 19s
host-win (armv7)	37s
host-x86 (x86_64, g++-10)	2m 0s
host-arm (armv7, none, none, clang++-11)	3m 20s
host-win (aarch64)	54s
host-x86 (x86_64, clang++-11)	55s
host-arm (aarch64, none, none, g++-10)	2m 45s
host-arm (aarch64, none, none, clang++-11)	3m 23s
host-arm (aarch64, crypto+crc, none, g++-10)	3m 4s
host-arm (aarch64, crypto+crc, none, clang++-11)	3m 23s
host-arm (armv7, none, -mcpu=cortex-a32 -mfpu=neon-fp-armv8, g++-10)	3m 13s
host-arm (armv7, none, -mcpu=cortex-a32 -mfpu=neon-fp-armv8, clang++-11)	3m 21s
test-win-msvc	44s
	33m 4s

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