rpm -> deb doesn't fail when optional packages are missing

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: szubersk <szuberskidamian@gmail.com>
Closes openzfs#13331
Closes openzfs#13336

config/deb.am

@@ -61,8 +61,8 @@ deb-utils: deb-local rpm-utils-initramfs
 	pkg7=$${name}-test-$${version}.$${arch}.rpm; \
 	pkg8=$${name}-dracut-$${version}.noarch.rpm; \
 	pkg9=$${name}-initramfs-$${version}.$${arch}.rpm; \
-	pkg10=`ls python*-pyzfs-$${version}* | tail -1`; \
-	pkg11=pam_zfs_key-$${version}.$${arch}.rpm; \
+	pkg10=`ls python3-pyzfs-$${version}.noarch.rpm 2>/dev/null`; \
+	pkg11=`ls pam_zfs_key-$${version}.$${arch}.rpm 2>/dev/null`; \
 ## Arguments need to be passed to dh_shlibdeps. Alien provides no mechanism
 ## to do this, so we install a shim onto the path which calls the real
 ## dh_shlibdeps with the required arguments.