base-files: don't include lib32 files for musl

Multilib on Void is already only supported on glibc[1] and as per the
musl libc FAQ[2] there is no ldconfig.

[1] https://docs.voidlinux.org/xbps/repositories/index.html#subrepositories
[2] https://wiki.musl-libc.org/faq.html

srcpkgs/base-files/template

@@ -1,7 +1,7 @@
 # Template file for 'base-files'
 pkgname=base-files
 version=0.143
-revision=3
+revision=4
 bootstrap=yes
 depends="xbps-triggers"
 short_desc="Void Linux base system files"
@@ -46,8 +46,8 @@ do_install() {
 		ln -snrf "${DESTDIR}/usr/lib" \
 			"${DESTDIR}/${d}${XBPS_TARGET_WORDSIZE}"
 	done
-	# Populate 32-bit lib files on 64-bit systems, for multilib.
-	if [ "${XBPS_TARGET_WORDSIZE}" = "64" ]; then
+	# Populate 32-bit lib files on 64-bit glibc systems, for multilib.
+	if [ "${XBPS_TARGET_WORDSIZE}" = "64" ] && [ "${XBPS_TARGET_LIBC}" = "glibc" ]; then
 		vmkdir usr/lib32
 		ln -snrf "${DESTDIR}/usr/lib32" "${DESTDIR}/lib32"
 		ln -sf ../lib/locale "${DESTDIR}/usr/lib32/locale"