Add support for vita target #318

Job	Run time
CheckTargets	1m 44s
Check (armv7-sony-vita-newlibeabihf)	38s
Docs	13s
Clippy	22s
MinimalVersions (ubuntu-latest)	40s
MSRV (ubuntu-latest)	4m 21s
MinimalVersions (macos-latest)	1m 2s
Nightly	37s
MinimalVersions (windows-latest)	1m 9s
MSRV (windows-latest)	6m 11s
Rustfmt	7s
Sanitizer (address)	1m 55s
Test (ubuntu-latest)	1m 42s
Sanitizer (leak)	1m 10s
TestPoll	1m 1s
Test (macos-latest)	1m 50s
TestWakerPipe	52s
Sanitizer (memory)	3m 9s
Test (windows-latest)	3m 37s
Sanitizer (thread)	1m 41s
Passed	1s
	34m 2s

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