fwhosts.cgi: properly fetch configured IPsec N2N subnets

fwhosts.cgi: properly fetch configured IPsec N2N subnets

Previously, the getcolor() function did not correctly process IPsec
N2N connections with more than one remote network configured, resulting
in networks mistakenly marked as being part of a VPN connection, or vice
versa.

Fixes: #11235
Signed-off-by: Peter Müller <peter.mueller@ipfire.org>
Acked-by: Stefan Schantl <stefan.schantl@ipfire.org>
Reviewed-by: Michael Tremer <michael.tremer@ipfire.org>
Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>