main/postmarketos-base: fix post-upgrade shellcheck warnings

Fixes 'SC2166 (warning): Prefer [ p ] && [ q ] as [ p -a q ] is not well defined.'

Signed-off-by: Aster Boese <asterboese@mailbox.org>
Part-of: <https://gitlab.postmarketos.org/postmarketOS/pmaports/-/merge_requests/9471>

main/postmarketos-base/APKBUILD

@@ -1,7 +1,7 @@
 # Co-Maintainer: Achill Gilgenast <achill@achill.org>
 maintainer="Clayton Craft <clayton@craftyguy.net>"
 pkgname=postmarketos-base
-pkgver=68
+pkgver=69
 pkgrel=0
 pkgdesc="Meta package for minimal postmarketOS base"
 url="https://postmarketos.org"

main/postmarketos-base/postmarketos-base.post-upgrade

@@ -9,9 +9,9 @@ if mount | grep "on /lib" ; then
     exit 0
 fi
 
-if [ -d /bin -a ! -L /bin ] || \
-       [ -d /sbin -a ! -L /sbin ] || \
-       [ -d /lib -a ! -L /lib ]; then
+if [ -d /bin ] && [ ! -L /bin ] || \
+       [ -d /sbin ] && [ ! -L /sbin ] || \
+       [ -d /lib ] && [ ! -L /lib ]; then
     echo "INFO: /usr merge dryrun to check for errors"
     if merge-usr --dryrun ; then
         echo "INFO: Doing the /usr merge"