Dont use EV_SYSFLAGS on OpenBSD #502

Job	Run time
Docs	14s
Clippy	16s
MinimalVersions (ubuntu-latest)	20s
CheckTargets (aarch64-apple-darwin)	34s
MinimalVersions (macos-latest)	26s
CheckTargets (aarch64-apple-ios)	31s
MinimalVersions (windows-latest)	53s
MSRV (ubuntu-latest)	12s
Nightly	19s
MSRV (macos-latest)	17s
CheckTargets (aarch64-apple-tvos)	33s
MSRV (windows-latest)	32s
CheckTargets (aarch64-apple-visionos)	31s
Rustfmt	12s
CheckTargets (aarch64-linux-android)	31s
CheckTargets (aarch64-unknown-openbsd)	32s
Sanitizer (address)	45s
Test (ubuntu-latest)	49s
Sanitizer (leak)	40s
CheckTargets (arm-linux-androideabi)	30s
TestPoll	36s
Test (macos-latest)	50s
Sanitizer (memory)	1m 8s
CheckTargets (arm64_32-apple-watchos)	32s
Test (windows-latest)	1m 38s
Sanitizer (thread)	44s
TestWakerPipe	33s
CheckTargets (armv7-sony-vita-newlibeabihf)	31s
CheckTargets (i686-unknown-linux-gnu)	30s
CheckTargets (sparcv9-sun-solaris)	31s
CheckTargets (wasm32-wasi)	25s
CheckTargets (x86_64-apple-darwin)	31s
CheckTargets (x86_64-apple-ios)	30s
CheckTargets (x86_64-pc-solaris)	30s
CheckTargets (x86_64-pc-windows-msvc)	30s
CheckTargets (x86_64-unknown-dragonfly)	29s
CheckTargets (x86_64-unknown-freebsd)	32s
CheckTargets (x86_64-unknown-illumos)	30s
CheckTargets (x86_64-unknown-linux-gnu)	31s
CheckTargets (x86_64-unknown-linux-musl)	30s
CheckTargets (x86_64-unknown-netbsd)	31s
CheckTargets (x86_64-unknown-openbsd)	34s
CheckTargets (x86_64-unknown-redox)	33s
Passed	1s
	23m 47s

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