File Makefile.patch of Package nx-libs
diff -Pdpru nx-libs-3.5.99.22.orig/Makefile nx-libs-3.5.99.22/Makefile
--- nx-libs-3.5.99.22.orig/Makefile 2019-08-27 15:46:39.000000000 +0200
+++ nx-libs-3.5.99.22/Makefile 2021-06-11 11:04:34.171370535 +0200
@@ -24,7 +24,7 @@ SHLIBDIR ?= $(LIBDIR)
NXLIBDIR ?= $(SHLIBDIR)/nx
USRLIBDIR ?= $(NXLIBDIR)/X11
INCLUDEDIR ?= $(PREFIX)/include
-CONFIGURE ?= ./configure --prefix="$(PREFIX)"
+CONFIGURE ?= ./configure --prefix="$(PREFIX)" --libdir="$(LIBDIR)"
# check if the xkbcomp devel pkg is available - we need it for the next step
ifneq ($(shell pkg-config --exists xkbcomp && echo yes), yes)