libselinux: rework selabel_file(5) database #610

Job	Run time
build (gcc, 3.12, 3.3)	1m 33s
build (gcc, 3.12, 3.3, test-flags-override)	1m 25s
build (gcc, 3.12, 3.3, test-debug)	1m 22s
build (gcc, 3.12, 3.3, linker-bfd)	1m 29s
build (gcc, 3.12, 3.3, linker-gold)	1m 32s
build (gcc, 3.11, 3.3)	1m 30s
build (gcc, 3.10, 3.3)	1m 54s
build (gcc, 3.9, 3.3)	1m 36s
build (gcc, 3.8, 3.3)	2m 8s
build (gcc, 3.7, 3.3)	1m 47s
build (gcc, pypy3.7, 3.3)	2m 10s
build (gcc, 3.12, 3.2)	1m 36s
build (gcc, 3.12, 3.1)	2m 25s
build (gcc, 3.12, 3.0)	1m 32s
build (gcc, 3.12, 2.7)	1m 48s
build (gcc, 3.12, 2.6)	2m 22s
build (gcc, 3.12, 2.5)	1m 51s
build (clang, 3.12, 3.3)	2m 42s
build (clang, 3.12, 3.3, test-flags-override)	1m 33s
build (clang, 3.12, 3.3, test-debug)	1m 27s
build (clang, 3.11, 3.3)	2m 11s
build (clang, 3.10, 3.3)	1m 48s
build (clang, 3.9, 3.3)	1m 39s
build (clang, 3.8, 3.3)	1m 49s
build (clang, 3.7, 3.3)	1m 53s
build (clang, pypy3.7, 3.3)	2m 3s
build (clang, 3.12, 3.2)	1m 45s
build (clang, 3.12, 3.1)	1m 46s
build (clang, 3.12, 3.0)	1m 40s
build (clang, 3.12, 2.7)	1m 52s
build (clang, 3.12, 2.6)	1m 54s
build (clang, 3.12, 2.5)	1m 53s
build (gcc, 3.12, 3.3, sanitizers)	2m 0s
	59m 55s

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