depext: relax OpenBSD lookup for installed packages #4003

Job	Run time
Analyse	7s
Cygwin	6s
Build-macOS (4.14.2)	3m 43s
Build-Linux (4.08.1)	2m 13s
Build-macOS (5.2.0)	3m 10s
Build-Linux (4.09.1)	2m 9s
Hygiene	13s
Build-Linux (4.10.2)	2m 45s
Test-macOS (4.14.2)	31m 15s
Build-Linux (4.11.2)	2m 12s
Test-macOS (5.2.0)	30m 11s
Build-Linux (4.12.1)	2m 14s
Build-Linux (4.13.1)	2m 7s
Build-Linux (5.0.0)	2m 16s
Build-Linux (5.1.1)	2m 16s
Build-Linux (4.14.2)	2m 12s
Build-Linux (5.2.0)	1m 59s
Build-Windows (x86_64-pc-cygwin, x86_64-pc-cygwin, 4.14.2)	36m 5s
Build-Windows (i686-w64-mingw32, x86_64-pc-cygwin, 4.14.2)	40m 4s
Build-Windows (x86_64-w64-mingw32, x86_64-pc-cygwin, 4.14.2)	39m 0s
Build-Windows (i686-pc-windows, x86_64-pc-cygwin, 4.14.2)	44m 16s
Build-Windows (x86_64-pc-windows, x86_64-pc-cygwin, 4.14.2)	42m 52s
Build-Windows (x86_64-w64-mingw32, x86_64-pc-cygwin, 5.2.0)	38m 43s
Cold-Linux	5m 3s
Doc-Linux (4.14.2)	1m 18s
Doc-Linux (5.2.0)	1m 11s
Test-Linux (4.14.2)	17m 3s
Solvers-Linux (z3, 4.14.2)	1m 5s
Upgrade-Linux (4.14.2)	1m 32s
Test-Linux (5.2.0)	15m 27s
Solvers-Linux (z3, 5.2.0)	54s
Upgrade-Linux (5.2.0)	2m 5s
Solvers-Linux (0install, 4.14.2)	1m 30s
Solvers-Linux (0install, 5.2.0)	1m 25s
Solvers-macOS (z3, 4.14.2)	13m 18s
Solvers-macOS (z3, 5.2.0)	15m 37s
Upgrade-macOS (4.14.2)	1m 48s
Solvers-macOS (0install, 4.14.2)	1m 36s
Upgrade-macOS (5.2.0)	2m 15s
Solvers-macOS (0install, 5.2.0)	1m 35s
	6h 56m 50s

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