[9front] mklib, upas/common: clean up libcommon properly

[9front] mklib, upas/common: clean up libcommon properly

[mikan]

Despite pervious efforts, mk clean still doesn't remove libcommon.a*
files from cmd/upas/common/.
To fix this, let's tell cmd/mklib to do the job instead:
Remove CLEANFILES from cmd/upas/common/mkfile
Add *.a[$OS] to clean rule in cmd/mklib

diff -r 40a5f1266803 sys/src/cmd/mklib
--- a/sys/src/cmd/mklib	Tue Feb 02 07:21:47 2021 -0800
+++ b/sys/src/cmd/mklib	Tue Feb 02 20:05:11 2021 +0000
@@ -39,7 +39,7 @@
 	rm -f *.[$OS] y.tab.? y.output y.error $CLEANFILES $LIB
 
 clean:V:
-	rm -f *.[$OS] y.tab.? y.output y.error $CLEANFILES
+	rm -f *.[$OS] *.a[$OS] y.tab.? y.output y.error $CLEANFILES
 
 %.acid:V:
 	$CC $CFLAGS -a `{basename $stem .$objtype}^.c >$target
diff -r 40a5f1266803 sys/src/cmd/upas/common/mkfile
--- a/sys/src/cmd/upas/common/mkfile	Tue Feb 02 07:21:47 2021 -0800
+++ b/sys/src/cmd/upas/common/mkfile	Tue Feb 02 20:05:11 2021 +0000
@@ -15,6 +15,4 @@
 	common.h\
 	sys.h\
 
-CLEANFILES=libcommon.a[$OS]
-
 </sys/src/cmd/mklib

Re: [9front] mklib, upas/common: clean up libcommon properly

[Amavect]

rc doesn't expand regexp inside variables, which was my mistake.
Changeset 8293 seems to indicate that we want to clean the local libs, while nuke is for removing the syslibs. So, I think this is a good patch.
For completeness, we should also remove the CLEANFILES from other local lib mkfiles.

Thanks,
Amavect