pkg/55847: python38 install hangs on i386

[Onno van der Linden <o.vd.linden%quicknet.nl@localhost>]

>Number:         55847
>Category:       pkg
>Synopsis:       python38 install hangs on i386
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    pkg-manager
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Dec 06 15:35:00 +0000 2020
>Originator:     Onno van der Linden
>Release:        NetBSD 9.99.77
>Organization:
>Environment:
System: NetBSD sheep 9.99.77 NetBSD 9.99.77 (GENERICSHEEPKMS) #0: Sun Dec 6 14:31:07 CET 2020 onno@sheep:/usr/src/sys/arch/i386/compile/GENERICSHEEPKMS i386
Architecture: i386
Machine: i386
>Description:
Build python38 on this machine which has low entropy. During the install of the python38 package

PYTHONPATH=/usr/obj/lang/python38/work/.destdir/usr/pkg/lib/python3.8 LD_LIBRARY_PATH=/usr/obj/lang/python38/work/Python-3.8.6 ./python -E -Wi /usr/obj/lang/python38/work/.destdir/usr/pkg/lib/python3.8/compileall.py -j0 -d /usr/pkg/lib/python3.8 -f -x 'bsd_coding|badsyntax|site-packages|lib2to3/tests/data' /usr/obj/lang/python38/work/.destdir/usr/pkg/lib/python3.8

is executed and it hangs. 

dmesg shows:
[  1081.260084] entropy: pid 20171 (python) blocking due to lack of entropy

>How-To-Repeat:
	Build python38 on a recent (9.99.x since May 2020) low entropy NetBSD system
>Fix:
	Changed -j0 into -j1 in the 4 calls to compileall.py in the python3.8 Makefile
	No idea if there's a more subtle way to handle this