plan9port: fix introduced typo

[Paolo Vincenzo Olivo <vms%retrobsd.ddns.net@localhost>]

Module Name:	pkgsrc-wip
Committed By:	Paolo Vincenzo Olivo <vms%retrobsd.ddns.net@localhost>
Pushed By:	vms
Date:		Fri Nov 25 10:46:21 2022 +0100
Changeset:	a9a695fd801fa983b0a7c00cffaefa9cbfac7827

Modified Files:
	plan9port/Makefile

Log Message:
plan9port: fix introduced typo

To see a diff of this commit:
https://wip.pkgsrc.org/cgi-bin/gitweb.cgi?p=pkgsrc-wip.git;a=commitdiff;h=a9a695fd801fa983b0a7c00cffaefa9cbfac7827

Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.

diffstat:
 plan9port/Makefile | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diffs:
diff --git a/plan9port/Makefile b/plan9port/Makefile
index f3743c9876..448db73946 100644
--- a/plan9port/Makefile
+++ b/plan9port/Makefile
@@ -77,11 +77,11 @@ DOCDIR=		${PREFIX}/share/doc/plan9
 
 MAKE_DIRS+=		${PKG_SYSCONFDIR}/profile.d
 
-PLAN9_BUILD=		${DESTDIR}${PLAN_TARGET}
-INSTALL_ENV+=		PLAN9_TARGET=${PLAN_TARGET}
+PLAN9_BUILD=		${DESTDIR}${PLAN9_TARGET}
+INSTALL_ENV+=		PLAN9_TARGET=${PLAN9_TARGET}
 
 .include "../../mk/bsd.prefs.mk"
-.if exists(/dev/kmem) && !empty${OPSYS:M*BSD}
+.if exists(/dev/kmem) && ${OPSYS:M*BSD}
 SETUID_ROOT_PERMS?=	${REAL_ROOT_USER} kmem 2755
 SPECIAL_PERMS+=		${PLAN9_TARGET}/bin/auxstats ${SETUID_ROOT_PERMS}
 .endif